I went ahead and removed that rule.
As far as Hairpin NAT, it is the first time I've heard about this unfortunately. After reading up on it a bit, unifi "should" have the rules on automatically but I do not know how to check but I kind of understand what you're saying.
My son would be playing on his PS5, but it doesn't have a choice for selecting LAN so I cannot really test it that way. The only other people that would join are a few cousins which are also on PS5s and me (PC).
Is there any way I could test that the Hairpin NAT is working?
Thank you so much!