As mentioned here.
I suspect this raises an interesting question, who is responsible for the TDE keys, especially when it comes to long term-term backup retention as Microsoft automatically rotates these certificates at least every 90 days and I suspect the underlying server will change at some stage.
According to this it shouldn’t be an issue.
’10. Q: I have TDE enabled for my database. Can I use TDE with the vault?
A. Yes, TDE is supported. You can restore the database from the vault even if the original database no longer exists.