[AndMetal]

Pet commands are handled in zone/client_packet.cpp:

void Client::Handle_OP_PetCommands(const EQApplicationPacket *app)
{
	char val1[20]={0};		
	PetCommand_Struct* pet = (PetCommand_Struct*) app->pBuffer;
	Mob* mypet = this->GetPet();
	if(!mypet) return;
	
	if(mypet->GetPetType() == petAnimation && (pet->command != PET_HEALTHREPORT && pet->command != PET_GETLOST) && !GetAA(aaAnimationEmpathy))
		return;
	
	// just let the command "/pet get lost" work for familiars
	if(mypet->GetPetType() == petFamiliar && pet->command != PET_GETLOST)
		return;
	
	switch(pet->command) {
	case PET_ATTACK: {
		if (!target)
			break;
		if (target->IsMezzed()) {
			Message_StringID(10, CANNOT_WAKE, mypet->GetCleanName(), target->GetCleanName());
			break;
		}
		if((mypet->GetPetType() == petAnimation && GetAA(aaAnimationEmpathy) >= 2) || mypet->GetPetType() != petAnimation) {
			if (mypet->GetHateTop()==0 && target != this && DistNoRootNoZ(*target) <= (RuleR(Pets, AttackCommandRange)*RuleR(Pets, AttackCommandRange))) {
				mypet->SetHeld(false); //break the hold and guard if we explicitly tell the pet to attack.
				mypet->SetPetOrder(SPO_Follow);
				zone->AddAggroMob();
				mypet->AddToHateList(target, 1);
				Message_StringID(10, PET_ATTACKING, mypet->GetCleanName(), target->GetCleanName());
			}
		}
		break;
	}
	case PET_BACKOFF: {
		if((mypet->GetPetType() == petAnimation && GetAA(aaAnimationEmpathy) >= 3) || mypet->GetPetType() != petAnimation) {
			mypet->Say_StringID(PET_CALMING);
			mypet->WhipeHateList();
		}
		break;
	}
	case PET_HEALTHREPORT: {
		Message_StringID(10, PET_REPORT_HP, ConvertArrayF(mypet->GetHPRatio(), val1));
		mypet->ShowBuffList(this);
		//Message(10,"%s tells you, 'I have %d percent of my hit points left.'",mypet->GetName(),(int8)mypet->GetHPRatio());
		break;
	}
	case PET_GETLOST: {
		if (mypet->Charmed())
			break;
		if (mypet->GetPetType() == petCharmed || !mypet->IsNPC()) {
			// eqlive ignores this command
			// we could just remove the charm
			// and continue
			mypet->BuffFadeByEffect(SE_Charm);
			break;
		} else {
			SetPet(NULL);
		}

		mypet->Say_StringID(PET_GETLOST_STRING);
		mypet->CastToNPC()->Depop();

		// WildcardX: Oddly, the client (Titanium) will still allow "/pet get lost" command despite me adding the code below. If someone can figure that out, you can uncomment this code and use it.
		/*
		if((mypet->GetPetType() == petAnimation && GetAA(aaAnimationEmpathy) >= 2) || mypet->GetPetType() != petAnimation) {
		mypet->Say_StringID(PET_GETLOST_STRING);
		mypet->CastToNPC()->Depop();
		}
		*/

		break;
	}
	case PET_LEADER: {
		mypet->Say_StringID(PET_LEADERIS);
		break;
	}
	case PET_GUARDHERE: {
		if((mypet->GetPetType() == petAnimation && GetAA(aaAnimationEmpathy) >= 1) || mypet->GetPetType() != petAnimation) {
		if(mypet->IsNPC()) {
			mypet->SetHeld(false);
			mypet->Say_StringID(PET_GUARDINGLIFE);
			mypet->SetPetOrder(SPO_Guard);
			mypet->CastToNPC()->SaveGuardSpot();
		}
		}
		break;
	}
	case PET_FOLLOWME: {
		if((mypet->GetPetType() == petAnimation && GetAA(aaAnimationEmpathy) >= 1) || mypet->GetPetType() != petAnimation) {
		mypet->SetHeld(false);
		mypet->Say_StringID(PET_FOLLOWING);
		mypet->SetPetOrder(SPO_Follow);
		mypet->SendAppearancePacket(AT_Anim, ANIM_STAND);
		}
		break;
	}
	case PET_TAUNT: {
		if((mypet->GetPetType() == petAnimation && GetAA(aaAnimationEmpathy) >= 3) || mypet->GetPetType() != petAnimation) {
		Message(0,"%s says, 'Now taunting foes, Master!",mypet->GetCleanName());
		mypet->CastToNPC()->SetTaunting(true);
		}
		break;
	}
	case PET_NOTAUNT: {
		if((mypet->GetPetType() == petAnimation && GetAA(aaAnimationEmpathy) >= 3) || mypet->GetPetType() != petAnimation) {
		Message(0,"%s says, 'No longer taunting foes, Master!",mypet->GetCleanName());
		mypet->CastToNPC()->SetTaunting(false);
		}
		break;
	}
	case PET_GUARDME: {
		if((mypet->GetPetType() == petAnimation && GetAA(aaAnimationEmpathy) >= 1) || mypet->GetPetType() != petAnimation) {
		mypet->SetHeld(false);
		mypet->Say_StringID(PET_GUARDME_STRING);
		mypet->SetPetOrder(SPO_Follow);
		mypet->SendAppearancePacket(AT_Anim, ANIM_STAND);
		}
		break;
	}
	case PET_SITDOWN: {
		if((mypet->GetPetType() == petAnimation && GetAA(aaAnimationEmpathy) >= 3) || mypet->GetPetType() != petAnimation) {
		mypet->Say_StringID(PET_SIT_STRING);
		mypet->SetPetOrder(SPO_Sit);
		mypet->SetRunAnimSpeed(0);
		if(!mypet->UseBardSpellLogic())	// solar: maybe we can have a bard pet
			mypet->InterruptSpell(); //Baron-Sprite: No cast 4 u. // neotokyo: i guess the pet should start casting
		mypet->SendAppearancePacket(AT_Anim, ANIM_SIT);
		}
		break;
	}
	case PET_STANDUP: {
		if((mypet->GetPetType() == petAnimation && GetAA(aaAnimationEmpathy) >= 3) || mypet->GetPetType() != petAnimation) {
		mypet->Say_StringID(PET_SIT_STRING);
		mypet->SetPetOrder(SPO_Follow);
		mypet->SendAppearancePacket(AT_Anim, ANIM_STAND);
		}
		break;
	}
	case PET_SLUMBER: {
		if(mypet->GetPetType() != petAnimation) {
		mypet->Say_StringID(PET_SIT_STRING);
		mypet->SetPetOrder(SPO_Sit);
		mypet->SetRunAnimSpeed(0);
		if(!mypet->UseBardSpellLogic())	// solar: maybe we can have a bard pet
			mypet->InterruptSpell(); //Baron-Sprite: No cast 4 u. // neotokyo: i guess the pet should start casting
		mypet->SendAppearancePacket(AT_Anim, ANIM_DEATH);
		}
		break;
	}
	case PET_HOLD: {
		if(GetAA(aaPetDiscipline) && mypet->IsNPC()){
			mypet->Say("I will hold until given an order, master.");
			mypet->WhipeHateList();
			mypet->SetHeld(true);
			mypet->SetPetOrder(SPO_Guard);
			mypet->CastToNPC()->SaveGuardSpot();
		}
	}
	default:
		printf("Client attempted to use a unknown pet command:\n");
		break;
	}
}

I believe you should be able to add a check like this for each command that they shouldn't be able to respond to:

if (mypet->IsFeared()) break;

So, to fix /pet back specifically, after

	case PET_BACKOFF: {

add

		if (mypet->IsFeared()) break;

If I'm not mistaken, we'll need to do the same thing for /pet attack, /pet get lost, /pet guard here, /pet follow, /pet guard me, /pet sit, /pet stand, /pet slumber, and /pet hold. I think that just leaves us with /pet health, /pet leader, and /pet taunt.