Sorry for being late...
My take on this is:
Mudokons, Sligs and Glukkons come from their Queen, which I believe only had to be fertilized once.
Vykkers reproduce like those flowers that have both male and female organs, I'm too lazy to look up the official name for that.
About the fuzzles, orally seems like a sound theory to me, albeit it is kinda...weird. But when you think about it, is there really another way? Since they'd just fall off each other...Or maybe I'm ignoring some biology principle here...never was my best subject, sorry...
So yeah, in a nutshell, that is what has always been my conception of OW reproduction. Correct me if I'm wrong