It’s easy to say - he should have done this or that. I see nothing wrong w/what he said. It’s the touchy feelie crowd, the company feeled they would be less threatened if they fired a Christian instead of a lesbo.
Hope he gets a good lawyer!
This has been the law for decades, there is no lawsuit here for him. Religious, racial or sexual discussions or preferences do not belong in a business environment. Check any work manual. Another widely known but not always published is “don’t dip your pen in the company ink”.