Heatwave was extremely skeptical about having another human just enter the academy, which was confusing to the others till he recalled when the academy blew up again for the second time during construction.
they didn't question how exactly Heatwave found out about it happening for the second time but when recalling the moment, Heatwave did have every right to worry about it. When the academy blew up when they were trying to fix it from the first one, it ended up happening because there was something wrong with the database. with someone not being in the database, Elma randomly went to a protocol and basically blew up the academy for the second time.
so, they had to add Wes to it so they wouldn't risk the academy doing a round three of turning into a disaster of explosions, which ended up taking very long to work because the internet connection was extremely slow for no reason and Elma was updating at the exact same time as it as being sent through to the point that Heatwave nearly threw a chair across the room.
By the end of it, everyone could literally tell that they should've just risked it and brought Wes in without going through that entire process because it wouldn't have been this long to do. Even with Wes now being in the database, he was technically still allowed to visit since they were not about to go and delete it when it took as long as it did.