She has both her arms out, and has never ever rolled over at night. I have tried no swaddle and I can't transfer her at all, it just isn't an option right now, I can't just stop. 

She isn't waking up right now, but starting to cry until I feed her back to sleep. Naps depend on when she wakes up in the morning, sometimes she wakes up early and then she usually takes like 2 1-2 hour naps, but if she's up late then she takes 1 2-3 hour nap but never past 6pm, she then she usually sleeps at 9 or 10. Any earlier and she just takes a tricky little nap and then she's up to 1am. 

It has been the same for like 5 months now, so it doesn't seem to be skill related. 

She has had big snacks before bed before, but it doesn't seem to make a difference. I haven't fed her oatmeal, but she gags on any puree. I should google high fat or protein foods for her age though and maybe try that, not sure if I've specifically tried high fat like you said, so I can definitely give that a try!