When a relationship is opened there are many things that used to be strictly defined that are suddenly redefined and sometimes the lines are thin and blurred.... Before you began swinging, if either one of you had sex with another person it would automatically be cheating. What about contact? If you had met someone and shared a kiss before you were swinging would that have been cheating?... for some people this is a straight up yes, others a not really, and some might want a divorce over this.
But now you've opened the wide world of open relationships. Welcome. It can be a very fun and exciting world for you and your husband, or it can be very difficult and painful. The difference is what you do with it. You have to talk with your husband openly and honestly. He already knows you're not interested in your girlfriend's hubby sexually. He gave you permission to go outside, but he sounds uneasy about this... as well he should be. You say you are very new to the openness of swinging. Obviously you have more trust within your relationship than most monogamous relationship couples have... but this can be difficult, even for more experienced swingers...
I have known couples who swing for 10 years and do not play without their mate... and others who swing for a year or two and play separately.
You and your husband need to have a chat with each other. No, a talk, talking is more serious than chatting... If you have not already discussed these things with him, now is the time to start.
Why not find another couple both of you can enjoy? I'm sure there's nothing wrong with your friend's guy, just not attracted to him. This is fine, swingers don't have to be attracted to everyone.. swinger does not equal nympho by any means.
Why does your husband not want to know before you'd play with this younger man? Is he jealous? Does he think he'll put a kibosh to the whole thing if he knows before hand?
Just this sends a red flag up to me that he is not really comfortable with this, but he's trying to make you happy.
Would you be comfortable with him playing outside of your circle? Why or why not?
Is there any chance your husband, yourself, and your new guy friend could play together? This might make your husband feel more comfortable that you're not going to leave him for this young stud.
Out of curiosity, the party you met this young man at, was this a swing party? Is this a swing party you may meet up with him at this weekend?
If it is going to be a swing party, this would be a good time to have a 3some.
Also, it sounds to me like you are faithful to your one couple that you play with. Is this a boundary line for either of you, or are you interested in playing with multiple couples (not necessarily at once, just having a few couples that you meet with for fun instead of just one) This would alleviate some of the discomfort from your situation of him getting satisfied with your friend and you not being satisfied with friend's hubby...
Then you need to talk about what you both agree on is cheating. Like I said earlier, some long time swingers don't play separately. For them, it's thin ice to tread on.. might be considered cheating, might not. You have to know what works for you.
If the situation were different, and you both enjoyed this other couple, would you play with him without your husband, or would your husband play with her without you?
Just figure things out for yourselves, what is uncomfortable, what is OK, and what is right out of the question. Then talk about the grey areas... this is where the most trouble can occur. If a grey area situation approaches and you're still not sure.. best to steer clear to avoid that iceberg.. might sink ya, might not, but do you want to find out?
Assure your husband you love him, are attracted to him and enjoy having sex with him. I hope he can do the same for you.