A new Subdomain is like a whole new instance. I would not move over old posts or something else.
Start completly fresh and have fun instead of headaches because of broken Posts 🌞
You can try your setup with another subdomain. This way you will see If there are any problems
And never lose your database. It is the heart of your instance, so do proper backups ☝🏻
Last update 2022, same with podgrab. I hope the dev is okay 🫤