James is an obvious guy to move on from. That draft pick was sheer desperation. The Dolphins were traumatized having dealt with Marc Colombo and Tyson Clabo and they made developing an in-house RT look like nuclear physics. So, they passed on Bradin Cooks and others to take a middling guy in James.
There hasn't been a bit of difference in the games where James has been out. That kind of irrelevancy does not lead to a nine million dollar contract.
Heck if the Dolphins threw this out there next year, would it hurt us:
LT Tunsil
LG Larsen
C Brendel
RG Davis
RT Sterup
or
LT Tunsil
LG Davis
C Larsen
RG Asiata
RT Smith
or
LT Tunsil
LG Larsen
C Pouncey
RG Davis
RT Smith
And that is without adding a veteran free agent interior lineman and a mid-tier draft pick.
James would not change the effect compared to these lineups. If he comes back for a comparatively small salary (say 50 or 60% of the laughable $9 million), he could be considered. But, really, where the real help is needed is on the interior of the line. Davis may even be a better tackle than guard. Right tackle presents itself with a number of options. The interior line is where there is a cracked foundation.