Important step, I believe they all mention, is to allow the tablo to first format the new drive - then copy.
It may seem more of a hassle with an internal drive - but necessary. Unless you’re using a cloning process of course.
If you’re lacking hardware to swap around internal drives there is a backup script. Backup-tablo.sh - Backup all recorded shows from a Tablo You could use that to backup your “old” drive and restore it to your “new” drive.