I'm not sure who you're referencing to here bro as I am not an avid Dolphins fan and depending on wheither or not he was a significant part of the team and when he started playing as in because of injury or some other factor that may have him not appearing on the roster.
This was expland a long,long time ago when these rosters were first created and input was given also some personal changes may be a factor in creating rosters because some guys start at the opening day of the season and some during certain periods in it due to injuries,trades,ect,ect, plus roster space in a video game comes at a premium as in limited roster slots given to a better more significant/worthy player who's contributed in other ways to the team for realistic results.
At one time in my earlier rosters he may have been there but you'll have to check them for yourself in the earlier threads I've done and updated to this point.
A little history or some info from you about this certain player would have been more helpful, again I'm not a Dolphin fan bro so clue me in or something.
Holla Back y'all
Rickster101