I would make a fake Facebook with no photos (make a fake Gmail and don't use your phone #) or anything and message the wife.
"Hey is your husband douche? I heard through the grapevine he is having an affair. I just thought I would let you know."
Then just forget about the account and move on. Don't give any details just short and sweet. Don't mention the cancer or false identity. Let God/Earth/Buddah whatever decide when she will read the message request and it's up to her from there.
Btw every relationship I've been in I've been cheated on. Thank you to all the women who reach out. We have to look out for each other. 🩷
I think he is so manipulative without evidence it would be difficult. I wish I could give screenshots with the pic in even though you can't properly see them she would surely recognise it.
The more I think about it the more it makes me sick. To not only cheat on his wife but then make up fake identities to perpetuate a lie he has cancer? To use his son's names and details of his genuine brother to further the lie. I remember the texts he'd send saying it was T's last chance at treatment because the chemo wasn't working to shrink the tumours etc.
This is a sign of a very sick individual. And on the face of it he seems completely normal / stable? Been married a long time, good stable job, two sons etc. What could possibly drive him to do something as heinous as this is beyond me.
So I'm not sure creating fake profiles and giving no other details would work. If he went to this trouble to manipulate me I'm sure he can with her.
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BTW might sound mad but I gave myself a timeline to get over this so to speak. After finding out the full story, i decided
February is a "free month" where I can mull over it and do what feels best in terms of if I want to stay in bed for the weekend eating chocolate I can. After that i want to draw a line under it. From March back working it at the gym, going on my walks and learning new recipes for tasty food. Once I'm back to feeling my best I might dip my toes into dating again. It gets brighter from spring anyway.
I know I can walk away from this knowing I was always 100% myself. It might make me more cynical and quicker to point out inconsistencies in future - but it hasn't made me bitter or would stop me from being open with someone more genuine.