Look, Felix. There's huge consequences when you start playing around with time. They have entire Investigation departments dedicated to making sure people don't screw things up too badly. It's really best to be careful especially when there's random doors connecting a Starfleet base to the Nexus.

"You told th-the captain?" Well, that's one worry dealt with and out of his hands. That's not worrisome in the slightest, having some human he barely knows inform the captain he's skipping work to play in transdimensional pockets. Then again, this Felix Caelus is a new crew member. They are supposed to look out for one another.

"I don't recall going through any special kind of door..."