would you smooth things over with someone who is a total ass?

[CowboysGal]

I'll try to be brief here without drip-feeding as I'd really appreciate some MN views and to find out WWYD.
I have received a text today from one of DHs friends apologising to me for the atmosphere at a wedding over the weekend.
DH has a large group of friends from school (7 of them so a group of 14 counting girlfriends and wives) and we all try to get together a couple of times a year. Last year one lad fell out with another over some money that was lent/borrowed and has never been paid back. The 2 were basically ignoring it as a way of dealing with it but it became obvious at get-togethers that it was unresolved. The men of the group take the view that it's not their business. A couple of us girls have spoken to the 'lenders' wife about it. She is,understandably, furious and thinks that the 'borrower' is not only behaving like a shit but is well out of order for not addressing it or apologising when we get together.
The wedding on Saturday was pretty weird. For the first time in 15 years the group were not sat socialising together. 3 couples were on holiday and couldn't be there, 1 couple were sat with family (it was their relative's wedding) and DH and I were sat with the 'lending' couple. The 'borrowing' couple were with other friends of theirs who had been invited to the reception.
So I get this text apologising to me and I don't know how to respond at all. This guy and I aren't especially close. I never see him outside of these group get-togethers and I'm one of the few wives/girlfriends who didn't know any of the group as teenagers (we are all mid 30s). I get on well with the lender's wife, the borrower's wife doesn't talk to me (possibly because I get on well with the other couple?) and it's quite clear she dislikes me.
DH thinks I should do whatever I want, basically doesn't want to be involved in any conflicts.
Part of me wants to tell this guy to man up and actually do the right thing by one of his oldest friends but then I also feel that maybe it's not my place to do that. I find it really odd that I have had this text while the couple he has fallen out with haven't heard from him. Surely apologising to them would smooth things over way more than apologising to me?

The text is from the borrow? I'd tell him it wasn't really my business and he's apologising to the wrong person.

Borrower, I mean.

yes, i would say,

'it isn't anything to do with me, and I am not comfortable not replying to your but that's all I can say'

end of

to your text*

yes all past years text is from the 'borrower'
I'd really like to tell him he shouldn't be apologising to me. That his apology elsewhere would probably have had more effect but then again I haven't heard his side of the story.
The facts I know are that he borrowed money, that he didn't pay it back, that it's caused an atmosphere between everyone at gatherings that used to be fun and easy and that his wife seems to have used my friendship with the 'lender' and his wife as an excuse to be really rude towards me.
Even though the issue is between 2 other couples I do feel as though I have been pulled into it. His apology to me makes me curious and also makes me think I have an opportunity here to maybe smooth things over a little. Would anyone else read into it that way?

Dunno really... I mean, I can see how his actions (or the lenders', as you say you don't really know the full story) have affected the relationships of others in your group, including you. But as for you smoothing things over, I don't see how you can - especially if you don't know the full story.

How about saying something like "I don't know what happened & don't need to, but it seems a shame to let an argument spoil things".

An outside chance that he is apologising for his 'd'w's rudeness?