Did giving up dairy help? Because if not, you could consider adding dairy back into your diet and trying eliminating gluten. I think it's a long shot it's a dietary issue at all but it's remotely possible.I did give up dairy. Giving up gluten too may be more than I can manage right now!
Also I would suggest still looking at ways to further improve the effects of the OALD. It sounds like you have improved the visible issues when the milk goes in, but if there is still a foremilk/hindmilk imbalance that is what could possibly cause gastrointestinal discomfort. It can take a long time for oald to go away.
Besides meds, what else have you done for reflux? Holding baby upright after feeding, burping, that kind of thing? With my second, he had to be upright after feedings due to reflux and oald. So at night, I would nurse him sidelying and then sort of prop him up against me, kind of lying over my side, so his head was above his tummy.
Also if I had a night I was done in, I would ask my husband to get up with the babies and walk them down in a sling. Sometimes they would go back to sleep, other times this would at least buy me another 30 or 40 winks. If your baby is nursing for comfort, he may accept other comfort measures some of the time.
I would also suggest that if you are well and truly done, and nothing is working, and you believe bottles at night would help, then do that. Is it the best idea purely from a breastfeeding standpoint? No, there are pitfalls to this course of action. But it may be the best idea for you and your situation, and may even help you nurse longer overall. If you want to keep nursing during the day & part of the night, try to give the bottles (or have someone else give the bottle, since this is supposed to be for increasing your sleep) in a breastfeeding supportive way and keep an eye out for nipple/flow preference, breast refusal, that kind of thing. Also If you choose to supplement with formula you will likely want to pump as needed to keep your supply appropriate.
Breastfeeding has benefits even if it is not exclusive breastfeeding, and personally, if I was in a situation where my only choices were to stop nursing altogether, or to supplement and be able to keep nursing longer, then I would choose the latter.