Exactly the same thing happened to me just with the difference that it was an Ops GF. Before I even managed to click "travel" I was removed from group by leader (because "our guildie came, sorry"...) and the message showed that I left GF and I'm now locked out for 15 minutes.
And no OP, it wasn't because of any ignore list. I whispered the leader asking "what the hell?", she admitted she kicked me because their guildie came for my place
It really, really sucks when players use groupfinder only to be removed by someone because of a "guildie"