The question is why the author felt the need to say two were “especially” close. Tom could have been close and not known it. Remember that at around this time, Exador and Ramses are walking around talking to each other. Tom could have been in a hallway one floor down and Talarius could be viewing them as close on his 2D mirror.
The other option of course is that Tom is so powerful he is ultraviolet and Talarius can’t see it on his mirror. I find that unlikely. I don’t think he has reached god status yet.