Dumbledore has been outed as gay - I never heard that Voldemort was outed as well.
Voldemort was who Dumbledore was in love with in his youth.
I wouldn't think so , Dumbledore was a lot older when he met the child Tom Riddle.
There is a caricter not introduced till the last book (no spoilers) that seems more likely because he and Dumbledore met at the same teen age.
But since they are all ficticious one may slander them at will with no fear of libel , ...I hope.