“Non Catholics, non Christians enter perfectly valid marriages every day.” Yes, valid under natural law.
??? Catholics may be part of a wedding party where either/both are non Catholic, even non-Christian.
Due to my concerns of giving scandal - not everyone is up to date with the Churchs viewpoint on such matters, nor on whether Catholics can or cannot attend other Faith services (otherwise if people were the OP for one would not be here asking the question), nor even very much on the Faith at all. All of which is very very obvious to me just by conversing with friends, others at Church, and family, so I thought base on this there was a
possibility of giving scandal.
The OP was initially concerned about giving scandal wrt the couples’ prior living arrangements etc, all of which I addressed in my posts. The only other
possible scenario that came to my mind was giving scandal in signing papers. And not all the key points were stated in the first posts, but were stated in following posts after questions were asked, so relevant info only came to light in dribs and drabs. At first I assumed the friend was possibly Catholic until a later post stating that wasn’t the case. So I was also trying to cover all bases at each point based on what info I had, not after reading
all posts and therefore having all info on which to comment. I also said in one of my posts wrt the signing of papers + scandal etc (post #17 that I honestly didn’t know if it is or isn’t). And in the same post I also linked to a post by InThePew concerning attending non-Catholic Events which helped to clarify matters for both the OP and myself, though I did point out Fathers comment didn’t mention being a member of the wedding party nor being a witness.
So rather than mislead someone and say it’s perfectly ok, and myself not knowing whether it was or wasn’t - I was erring on the side of caution, admitted I wasn’t sure, linked to a priests’ article, asked if the OP had consulted their
own priest on the matter.
Apologies if my best efforts didn’t meet your standard.