Hey there, I'm new to the forum but not new to sauna Thermas. I can answer from my experience.
1) There are certainly boys who agree to that. It's actually a fairly common thing that clients ask for, I've heard from speaking to the boys. The biggest chance of success is to already have a good "relation" with one of the guys and ask him to find another guy to join you. This way you know that the guys will enjoy working together.
2) Many are tops, yes. And there are tops who don't suck, so you have to ask. In my experience the boys who don't suck were always clear and honest that they didn't do it. They never said they would and then not do it.
Guys who told me they suck always did so. The biggest thing I've noticed they will go back on is kissing... They will tell you that they kiss but once in the cabin there's not a lot of(or even no) kissing.
3) The most sure way to have the boys suck in a group session is to ask them directly. I've not heard of happening, but always be clear in what you'd like to happen. I have heard of this in regards to bottoming, meaning that the guy will bottom when he's alone with the client, but will not bottom in a group setting with another guy present.
