well . they can't invite all.
They don't need us, they need people to buy their games, nothing more.
Once it's out we will take over and mutate it into something we like, and then, their gameplay is no more, hence their support will also be gone.
If i made a company and made a fortune on a game, then i would make another game when the first one stops sellings and don't look back ....
There are plenty of enthusiastic people who will be able and willing to support the old games, 8 years for UT99 is a long time for a game, way too long for us to expect anything from Epic.