I am far from being one of the experts out here, but here are a few observations:
1) If possible, I would try to negotiate away those exercise and assignment fees. With such a slim margin for profit, they will eat away at it. There are too many brokerages out there with no exercise or assignment fees.
2) I'm not so sure the value was ever 87.95 or even the mid 90s. You say you have had success in paper money but have you had this kind of success in realtime with 1 DTE?
The value being 87.95 is almost like having 800 point OTM 1 DTE SPX options trading at 0 x .05 and having one strike 750 points OTM 1 DTE bid at 1.00.
3) It seems unfair to them to restrict your account in this manner, unless, of course they perceive you as someone who "bets $100 on black and at the same time bets $100 on red." and perceive you as a total newbie. (0 or 00 will get you in the end!) If you have history of similar winning trades to show them, that would resolve the problem. Then again, why should you have to do so, right?
4) I don't know if you have done this, but I would try to speak to someone in person. The only thing not working in your favor is that you don't (as far as I know) have a long history with them and haven't given them huge commission amounts over the years. If you go nowhere speaking to a real human being, maybe it's time to go/remain elsewhere?
Perhaps others can chime in on this matter?