I do have a couple of questions before any advice.
1) If they had gotten tested and didn't have any STD/STIs why would he still need to use a condom? If you were concerned about sexual health if that part is already known to not be an issue why should condoms be needed?
2) If you were concerned about your sexual health why not, instead of telling him he needs to use a condom with other partners, decide that you and him would use condoms?
You know you don't want an intimate relationship with him. Yes, your trust was damaged. He was honest which was good. You need to learn how to separate what was a betrayal in your relationship from the trust you could have in a friend to be honest with you. Don't try to rush it. Give it a month or two and get to a point you aren't hurting from what happened in the relationship.
Woodsmith: My husband
Merry: Tig's wife/slave
N8: Merry's boyfriend/owner
Elle: N8 girlfriend
Ruby: Part of the Leather Family
Logan: Leather Sir in the Family
Arc: Logan's boy
Holly: Leather family
K: Holly's sub