Post-operative enucleation pain - ADVICE PLEASE

My cat had a right-sided enucleation performed on Tuesday, May 30th. I picked him up from the clinic on Wednesday July 1st.

I was told everything had gone very well, but that he had refused his meal on 7/1. I brought him home and he exhibited gagging, mouth pawing, and grimacing when attempting to eat. I called the clinic - they said the pain was likely due to the "weird" feeling in his socket and that he was still adjusting. Grooming also would trigger this response.

Two days later, July 3rd, and he continued to have the same response when eating/attempting to eat. I called the clinic again and was told the same - I expressed my concern regarding his hydration status and had to request that he come in for subcutaneous fluids. They were able to squeeze him. Vet tech administered fluids. She examined his mouth and did not see anything of concern. His surgical site looks good.

In the following days, I supplemented with puree being syringe fed to maintain caloric intake and hydration the best I could. He accepts syringe feeds with no gagging, grimacing, or any difficulty swallowing. He slowly had a return to his appetite and ability to eat when I found a cat food that he liked (I tried every brand and flavor variation before finding a winner).

He began to decline again Thursday into Friday. He was listless and there is very obvious weight loss. I asked for an emergency appointment. He was seen in office yesterday. The vet did a physical exam - he was afebrile. She suggested a skull x-ray which showed nothing of concern. His surgical site continues to look excellent, is healing well, and was non-tender on palpation. She was basically like "IDK man" and offered no plan or solution. I had to make suggestions - I asked about an appetite stimulant, an antiemetic if that was possible a component, and a corticoid steroid. She was willing to try this plan. I was so stressed and worried about him that I didn't even realize that she didn't order a CBC or CMP - no labs at all - no offer of another subcutaneous bolus. Now I am concerned about staring the corticoid steroid worrying that there is perhaps an occult infection and that this may exacerbate it. I worry the appetite stimulant will lead to further frustration as he is interested in eating/hungry (he paws at his treats and then refuses when offered after purring and rubbing his nose on them)

I am at the absolute end of my rope. He is taking gabapentin 100 mg BID since his surgery. I feel like this clinic is offering no real help. He has lost two pounds total from 14.5 -> 12.5. I am wondering is this is an appropriate treatment plan? I would go to an emergency clinic - however, I feel as though I should be able to depend on his vet to be thorough. I have spent thousands of dollar on his pre-op work-up, the actual procedure, and another $500 yesterday for a treatment plan I formulated myself. I don't know anything about vet med.

Any advice - or concern about this treatment plan, please let me know. I am begging you all. Thank you.

EDIT: the treatment plan is

5 mg prednisolone taper

Transdermal mirtazapine

Cerenia 8 mg

Continue gabapentin 100 mg BID

He will be going to the office on Tuesday for suture removal.