I'll try Miffer. It was said in the comments section something like that historically this group hasn't included LGB - I'm not sure why, I'm not au fait with whether this has any political implications.
Over this particular issue, one member of the panel was a lesbian who was had detransitioned and one was Miriam Ben-Shalom. The comment said that including two lesbians in the panel would aid their stance. I don't know the details as I was speed reading and not familiar with all the people in the group. Although I have heard of Miriam Ben-Shalom.
Presumably it was to present a united front.
Miriam was awesome - taking no prisoners. Someone called her a terf and she ripped back with 'no, I'm a perf !' (penis exclusionary) and maintained she'd had enough of 'swinging dicks' in the military.