This is, what the wiki says about this:
Tokens are rewarded at the completion of a dungeon path. The amount awarded is 60 tokens after the first run of each path on each character. Diminishing returns apply if the same path is completed repeatedly within the same day, and reduce the tokens rewarded by half.
So in the wiki the 2 hours aren't mentioned, but it also says "per each character".
Can anyone please confirm, that you get the full reward, if you use different characters and clarify, if you have to wait in between the two runs or not.