A sort of vip escort / versus hybrid.

There would be two submarine in the game, each starting at opposite ends of the map, just like in versus.
A crewmember in one of them would be poisoned by a slow acting poison (Around 8 minutes to be lethal.) The other submarine has the only antidote. The two crews would have to work together to reach each other as fast as possible, and Administer the antidote and have the player reach one of the stations in one piece. If the poisoned player dies at any time, the mission would fail.

Does this sound good? Please let me know what you think!

This sounds really good! It would probably be added as an expansion on the "Crewmember Poisoned with Morbusine" mission!
However, 8 minutes seems too short. This should work after 10 minutes. Other than that, this is good!