I'm an active grandpa diagnosted wiht EPI in 2016. I also was diagnosed with Type 2 Diabetes around the same time, so I had already modified my diet to watch carbohydrates and sugar. I lost 35 lbs before EPI was diagnosed. After about a year my GI doc said I probably don't need to worry about fat any more and haven't had any issues. My weight has been pretty stable since the dignosis.
I also wanted to speak with a nutritionist and asked my GP doc for a referral. The insurance co denied paying, and I called them to explain my situation and that it was after a doctor referral, not simply a request. It did get covered.