I am curious you say that this BP has not pooped and was fed 6 times, now based on that information I am not seeing anything abnormal.

Did the animal appeared to have a blockage in other words having a bulge near the vent area?

If the animal is constipated and has a bulge near the vent area, I can see being worried and taking measures otherwise I do not.

Those measures can be anything from warm bath followed by a gentle massage of the area, which can be repeated as needed.

You can also consider an enema which I am surprised the vet did not recommend.

If constipated and again I do not know since I have not seen the animal, it could be due to a large urate and the above method will likely work.