You won't get strikes if you join them and use songs that are covered under their cover program, not all songs period. MCNs used to be a place where you join and abuse the content id protection for profit, however those days are long over as youtube crashed hard on mcns last year and forced them to shut down subnetworks and institute a managed/affiliate program (only managed partners have no content id scan checks). It's why there was such an outrage by many people who use to use copyrighted content for gain and were left out in the cold (as any strikes affect the whole network under managed). There is no point in trying to pull the same stunt anymore, it's far more profitable actually trying to build content instead of reuploading/spamming other peoples videos.