I think those denominations would view their “new” attitude towards homosexuality in terms of it being a culturally-determined thing (like Jewish dietary laws), rather than a universal moral absolute, which is the RCC’s position. Which doesn’t make either position ipso facto correct, of course, but while some value a re-asserted inclusionism over customary teaching, others prefer the tradition. (I know which I prefer, which is why I ended up a Catholic). God lets us be in error all the time, remember (and be grateful every time you see a rainbow), so there is no reason to suppose He would have been particularly exercised about this issue. It’s not quite the same as turning to Baal, I think.
(Minor query-aside- does Judaic tradition go as far back as ~2000BC? I’m not aware of any evidence for it other than the somewhat suspect chronology of the Bible itself…).
Whichever position one holds, I think the purported prohibitions on homosexual activity is on a very different level from the direct matter of faith which is the Resurrection. I don’t think thinking that homosexual acts are “ok” with the Almighty makes one non-Christian (you might well be a Christian who isn’t advocating what God would want, but we can all be guilty of that some times)