I'm going to upgrade mine in the 3121 to the locking mount. The one they put in there isn't worth anything. I've beefed up walls like you mentioned before, but you should be fine if you screw the mount into one of those studs. On my father-n-laws camper, there wasn't a good spot. TV mount needed to go right in between 2 studs in the wall. I made a mounting board, same wood / stain/ trim and all, to match the cabinets. Screwed it into 2 wall studs, then the tv mount to the matching board. Just an option.
John and Rebecca Dickson
Emma-7 / Little John-5 / Iva-1
Full Timing Again, Rev B
2013 Ford F-350 Lariat CC LB PSD
2015 SOB TT - With OC's Awning Poles (#8)
At least in Heaven, RVs will be perfect, and I won't have to keep fixing them.