The send to Illustrator feature is not working in Fresco 2.7.2 for the iPad (iOS). It just displays a spinner control but doesn't actually send it to my open Illustrator app on the desktop (MacOS Big Sur 11.3.1)
It's completely broken, just doesn't work anymore...
Illustrator for Mac 25.3.1
Started to work, sometimes it works sometimes it doesn't
I tried and it's working fine for me. Can you restart your MacOS and see if it fixes the issue?
The more complex the document, the more chance of send to Illustrator to fail. It times out and never gets to "Document Sent" stage