Hi J-B,
Sorry that you've been unable to open a ticket - there has been some extreme weather across Texas today that has affected access to some of our services. Things seem to be stabilising from here now so you should be able to log back in again shortly.
Regarding your report, I reverted to a v8.1.1 installation here to reproduce the original bug in CORE-16265, I then applied the hotfix to confirm that this resolved the issue. Moving forward, I created a ticket from an 'Authorized User' and also from an 'Owner' user which both imported correctly - follow-up responses to both tickets also imported correctly, so as it stands I'm unable to reproduce this locally.
If you have any specific reproduction steps please do let me know in case I've missed something, otherwise I'd recommend opening a ticket with our team so that we can take a closer look at this for you.
-Jay