Including the part about not judging and treating others as we would like to be treated?Read Matthew.
A celebration which makes a mockery of the marriage context which Jesus describes as what God gave us, is no place for us.
Again, I have a real difficulty calling it a "marriage." So, if it isn't a "marriage" does that remove the issue for you?
As an aside, the last wedding my wife and I attended consisted of a couple millenials (heteros) getting married. It was strange. The "readings" were excerpts of poetry and modern writing that resonated with the bride and groom. There was an officiant who quoted the Bible, but that was the only mention of God. It was a neat, but non-religious ceremony, filed by a lovely reception in a neat venue.
But it didn't feel like a wedding to me.
Change that scenario to a gay couple, and I'm not sure it really would've changed much.