Meet Waffles the supposedly 3 year old normal ball python I got off craigslist. The previous owner died and the new owner could not care for him/her properly so I picked it up. Apparently it hasn't eaten in about over 4 months and was stuck in a piece of decor for the last week or so. I scheduled its first vet appointment already but it wont be for about 3 weeks. I am looking for advice on how much/how often to feed it to bring it back up to the proper weight for its size.

Age: about 3 years.
Weight: 300 grams.
Length: somewhere between 33" and 35".
Sex: unknown but probably male based on size and age.
Visible issues: underweight, possible stuck eye caps, dehydrated.
no evidence of respiratory infection or mites

It ate one adult mouse the day I got it home, but with it being soo thin I am worried about feeding it too large of a meal right away. I was thinking of feeding it 2 adult mice every 5 days for the next 10 - 15 days, then 1 50 gram rat every 7 days till its body condition improves. All the vet said when I called to set up my appointment was take it slow till the appointment. Does this seem like a good "take it slow" schedule or should I change it up. I plan on addressing the stuck eye caps tonight with a good soak and a wash cloth. Any recommendations on the stuck eye caps is also appreciated.

For reference my 8 month old male is also 300 grams and is eating 30 gram rats every 7 days.