New dentist if you are sure you are wearing the guard correctly. Sometimes mine moves around at night if I am restless.
Don't eat hard foods, bagels, chewy stuff. Pain may calm.
Go see John Shefferman. He fixed my TMJ (clencher( and DH (grinder). Guards do require tweaking to get them perfect so you go back a few times for checks.
Skip Botox until you see someone better.

I am struggling with jaw pain and looking for advice from others that have successfully managed this.

A few years ago, I was experiencing some minor jaw and ear pain on one side, and the ENT and dentist both immediately diagnosed grinding and recommended a mouthguard. Got the mouthguard; worked like a charm. Problem is that after a year, my dog somehow got the mouthguard off my counter and chewed it up.

I asked the dentist to make me another copy, but she said after a year they required a new mold, so I went in and got a new mouthguard a month or so later. After wearing the new mouthguard for about a month I ended up with such severe jaw pain that I could barely eat. Dentist told me they'd make a new mold, but make it much thinner. In the meantime, prescribed muscle relaxers and ibuprofen. Got the new mold, same pain. Stopped wearing it; jaw pain abated somewhat, but now having the ear pain I suffered from initially. She's now suggested botox shots in my jaw muscle. WTAF. Please tell me I can fix this nightmare somehow. Should I go to a new dentist or are there jaw specialists somewhere?