Everything seemed to be going as expected, I chose accounts to share each of my flows with to make others the co-owners. The accounts were both individual accounts as well as shared service accounts/mailboxes. The flows moved from the "My flows" tab to the "Shared with me tab" and were all listed there.
I went to one of the notifications in one of the shared mailboxes where it said that the account had been added to a flow. I clicked "View flow" from the email message and the flow was no longer there.
The messages on the page were:

Report
All responses (
Answers (