A) You haven't followed the requirements listed on that page, B) you seem to be using stuff that didn't come from there, C) there seem to be works on that site that are unlicenced derivatives - you would need to prove that you weren't using anything like that.
Viewing post in The Cold's Hold jam comments
You didn't make every effort possible to mention that site and the artists involved in the works you've used - you didn't even bother to mention that on the game's page as is explicitly required by the rules of this jam.
Looking at that site, it's very clear that there are some works hosted there that infringe upon the copyright of others and haven't yet received a DMCA takedown request. The onus is on you to prove that everything you have used has been licenced for that use by all copyright holders with stake in the work (not just the remix artist, and not just a website).