The TMJ dentist couldn't find anything wrong during exam of jaw he had some concern about being unable to move it from side 2 side left only thought?

Need expert opinion. General dentists often don't understand TMJ. See a TMJ expert for another opinion. Sounds like you have a TMJ problem.
Grinder? Your muscles may be in trismus or spasms due to trauma, a bad bite, grinding or clenching or a growth or something that is not allowing the muscles to function properly. A ct scan would be very helpful as well as a thorough bite and occlusion exam.
TMJ problem tough... Agree difficult to diagnose TMJ online: if u have pain but dds found nothing seriously wrong, u may just have muscle tightness/spasms from chronic bruxism. This is v. Common problem. If so, try ice packs side of face near the ear 20 mins on/ 20 off. Do this 2-3x. Then chng to warm moist heat pack x 20 mins. Try otc Ibuprofen 400mg every 6 hrs to help decr. Inflammation. "lipstogether teeth apart"!
Seek help. Are there any other symptoms . Migraines, tinnitus, why did you seek TMJ specialist when your jaw doesn't move to left usually means there is some kind of entrampment of your right joint ( opposite side) you may wish to seek a neuromuscular dentist in your area they shd be able to help.
More info needed. We would at least need more details if not to be able to actually examine you ourselves. Other symptoms, if any? Also not sure the experience, knowledge and expertise of the dentist doing the evaluation. If that was the only finding, i would just monitor it for now and not be too concerned. Again, it's hard to properly advise you over the internet.