Can multiple computers run a wallet at the same time, using the same license for mining?
Yes That's possible
yes, it is told about this opportunity in this document https://docs.google.com/document/d/1BOB3Xc5vHNKBNZJeosXGi0iNCxiD6rbFTvbF1uXfv10/edit#
it is specified on the 4th page
"Mining licenses are meant to be distributed between chapter members as they wish. A license can be installed in more than one miner software and it will make it mine until the miner cap is reached in either computer. This means that the system doesn’t allow cheating and that licenses can be shared between chapter members without causing any disruption. If a miner reaches the predefined cap it just stops and waits for the next mining period, sitting idle without consuming any resources of the computer where it is running."