I was in a similar situation, about to go back on pred to get rid of a stubborn 1 1/2 year flare.
if it was me, first I would try the cort ememas and keep a food and symptom diary before going to prednisone. If it were me, i would give that a couple of weeks , as long as i was about the level you mentioned bm's 4-5. if i became drastically worse i would call gi of course
I went on pred one time, felt better while on it but flared again within 2 weeks, so that is why i am not very excited about pred.
what helped the most was figuring out some of my food triggers and eliminating them
luckily, some of the things that i did helped me and I did not have to go on pred again