I agree on the Asmedia peek, that is something that is being improved upon in the "reset" with the expansion of the beginning of the game, so it should be more clear. That was actually somewhere I got stuck as well.
Sheila's card tells you exactly where to find her for The Call.
That signal has gone though several changes as it has caused confusion before. To give them the rooms all you need to do is visit each one of them in the handling room. Once their portal disappears then they can be found there. The nav is being reverted but in 0.58 you need to scroll to get to the handling room, in case you get stuck there.
Also as a request, if you could split the wall into paragraphs like this, it makes reading it much easier. Not just for me, but I'm guessing for most people.