Board Game Arena

I am now in a real time game of takeneko that will finish about 5 minutes past the start of a real time tournament. Do you know if one can be in 2 simultaneous real time games ?

You totally can't, and that's one of the main advantages of turn-based games. you can be in a lot of games at once.

The likely reason for that is, if you're in 2 turn-based games at once it will be much much easier to run out of time.