Jenkins' deal with GB has a $24M signing bonus and that's all the guaranteed money in his deal. If the Rams could get Dotson to sign a deal like that I'd be more than OK with it.
This is only Dotson's 4th year in the league and whether it's scheme, coaching, or just growing into the position the guy has arrived and could be a stud for the next 10 years.
I'd lock him up, especially considering that Jackson and Avila are still on their rookie deals and Shelton is relatively inexpensive. (Jackson's cap hit next year is under $1M, Avila's is just over $2M, Shelton's is $3M.)
Then when you consider that the Rams might want to upgrade center (maybe get a new center, maybe move Avila over and get a new LG) and/or move on from Noteboom I would think the Rams would want to minimize the turnover on the OL.
AlbaNY_Ram