Dinky,
Can I throw into the mix that even if, and I acknowledge that it's an if, some of the "indiscretions" were historical, for a CD'er who's lived in the closet for years, it's immensely difficult to admit to a former history. Having approval is a new starting line. However what's happened in the past still carries the same stigmas and guilt. Plus and this is in no way any fault of yours, he still may find it intensely difficult to admit to owning items of clothing/underwear that for possibly decades have been taboo. In effect it admits lying.
If it proves that those indiscretions weren't historical then that moves the goal posts tremendously. You've given the green light to be open and honest. To be accepting. Failure to be truthful is a game changer.
"Not forgetting the photos of him performing oral sex on another guy".
I can utterly understand your need to be absolutely certain that this took place prior to the start of your relationship. Otherwise this is just plain and ordinary cheating. I can understand that some will say that I as a closet CD'er in effect cheat on my SO. My response is any interaction I have with others due to my CD'ing is purely platonic and has no sexual only social content. If I could be absolutely certain that my SO would be as accepting as you have been, I'd out myself in an instant (at least to her)
