Heya, Sanya here.
I’ll try to answer your question best I can.
FreeDoom should be a free replacement for the Doom assets under a BSD license.
Still, I’d just doublecheck and make sure you replaced all the assets and remove the ones you don’t use just to keep things clean and spiffy.
And sirry for the off topic question
no need to be sorry. I am glad to help with questions like these.