It's not clear if the manager double-checked or made an educated guess, however it's probably safe to assume that the first Tech looked for the files "where they should be" and found nothing in your userspace and the initial logical reason for that (from their standpoint) would be that a technical failure of some description occurred during the migration.
The site was functioning normally when you last posted on it just a day ago, so the data and images were being loaded successfully from "somewhere" - so let's try to eliminate some possible "somewheres".
Did you create the website alone or did you employ assistance at any stage?
Was the WordPress site set up via the One-Click process? (There was an issue with it very recently).
You've already said you don't have an extra user account inside your Panel, but I'm going to ask that you take another quick peek by clicking on Users > Manage Users inside your Panel. The reason I ask is that sometimes users take advantage of directory remapping, and the wp-content might be something that could be remapped to another location for back-up purposes.
After ruling out the above possible points of failure...
You made mention in another thread that after conversing with Support about the missing website that "They emailed me (minimal) instructions with a non-working userid!". If I'm reading that correctly, then this is extremely troubling and is the reason I'm going to make this last seemingly ridiculous suggestion:
Ask Support to check the records to see if any other user on the louisa server was either moved or had their account closed recently. If so, ask if they could check where that user's data was moved to and request that they do a cursory search for your data at that user's new location.
I really hope you get all that data back.