If those tracks ever get an official release they only have historical value.
The two known tracks clearly show, that the chemistry between them did not really work.
"State of shock" was no great song, and although Freddie and Michael put in dozens of yeahs and screams the song did not come to life, it sounds very "forced". It was Jagger and Tina Turner at Live Aid, who really made it work.
I'm sure that both Michael and Freddie noticed that they did not function in a duett and that's the reason why these songs remained unreleased.