Wow, that is bizarre about the matriarch watching the marriage being consummated.
I agree that Vulcans can, and clearly some do, have sex outside of pon farr. Who am I to disagree with D.C. Fontana?
For what it's worth, Selar's brother was pretty emotional for a Vulcan. He seemed like the most well adjusted Vulcan I remember "seeing", which could be an alternate explanation for why he didn't go thru pon farr. I'm treating that as an individual situation that he specifically doesn't go thru pon farr instead of the wider suggestion that all gay Vulcans, or at least the males, don't go thru pon farr.