I wouldn't bother with such challenge when they don't respect GPLv3 which used by WifSolverCuda[1]. Besides, it's more sensible to rent GPU on remote server or ask professional instead which have lots of GPU.
Why is the program without source codes?
The correct ranges and other parameters are sewn into the WifSolverCuda program.
Knowing them, the user can find the key on his own and take everything for himself.
[1]
https://github.com/PawelGorny/WifSolverCuda/blob/main/LICENSE