I call bullshit. I’ve seen Fingers (maybe 20 times... I even (sadly) have a child named after one of them 😂.... probably a little too much information there
I only remember U2 and them playing one gig together and it was televised I think in 1981. Fingers were the bigger band then.
In 1978 U2 band members were still going to see SLF live
https://www.u2.com/news/title/kicking-up-a-racket/news/