I always wished this game came out,it was supposed to be a nice Standalone sequel for TFC https://wiki.teamfortress.com/wiki/Team_Fortress_2:_Brotherhood_of_Arms Too bad the time was not enough,It has more Teamwork then the Current TF2 .. * Do you think the Devs still have the SRC For the game ?
Yeah most definitely somewhere Valve has a build of the game locked away. Valve, from what I have seen, never really gets rid of anything as they usually have a feeling that they want to use it later. TF2: Brotherhood of Arms would of defiantly been an interesting game, sort of a Battlefield 1942 before that even came out. But, from what I have read that in 1999 when they originally showed it off at a gaming expo they had a playable build. Quite possibly it is floating around somewhere.
Years ago a Dev said "We we're unable to continue working on game because the time wasn't in our side, The engine was getting older and older but instead we converted the game to work with our new Source engine with Many changes, we thought that we should keep it a Free to play game like TFC Was years ago" That was the Main reason for it's Cancellation ,Though i'm not sure if they still have the older Source code .
I found that someone made a Brotherhood of Arms mod for Team Fortress Classic. I don't know if it's any good or not. http://www.moddb.com/mods/team-fortress-brotherhood-of-arms-mod
there was a half life mod that was very very similar to tf2 its called FRONTLINE FORCE http://www.moddb.com/mods/front-line-force
