I believe that in my post It was suggested that Lucian did send a party invite?

"Your invite should be appearing shortly, that is if non Gamers can be added to friend lists and invited into party" This was new terrain for Lucian, he had only ever fought with the other gamers, would it let Saito into the party? Not waiting to find out,"

that not waiting to find out meant that he went forward before receiving a notification that saito had joined the party.