DBATools is awesome for this:  Invoke-DbaDbClone

About the only time I see something like this is when I grabbed the wrong backup (an older one).  You are certain you grabbed the correct backup file?  Did you...

If the issue isn't DNS it's probably a Kerberos\SPN issue:

https://learn.microsoft.com/en-us/sql/relational-databases/native-client/features/service-principal-name-spn-support-in-client-connections?view=sql-server-ver15

You can use the MS Kerberos tool to check it:

https://www.microsoft.com/en-us/download/details.aspx?id=39046

Also, is the SQL Browser Service running?

Shouldn't it be IP, port   (comma not colon) ?

Rollbacks are single threaded so it can take much longer than than the parallel operation that got you there.

I would give 'dbcc updateusage' a try.  I can tell you this has fixed weird disk performance on new servers for me more than once.

https://learn.microsoft.com/en-us/sql/t-sql/database-console-commands/dbcc-updateusage-transact-sql?view=sql-server-ver16

#1.  Since nobody has responded, I'll offer maybe a bump in the right direction.  I've found SPN's are very important to SSRS.  I'd make sure you have a domain account...

In AD, did you give the service account the 'Trust for delegation'  property?

https://dbatools.io/    - makes this very simple

You can use 'Sync-DbaLoginPermission' (everything) or 'Export-DbaDbRole' (to get role)

Shrink it in smaller chunks.

Google for a script to reduce it incrementally.

https://www.sqlservercentral.com/blogs/sql-database-incremental-shrink-tsql

Shrink it in smaller chunks.

Google for a script to reduce it incrementally.

I'm now up to 10 failovers with no sync issues.  I'm also on CU22.

I hate to possibly jinx myself, but I've had 5 failovers with no secondaries out of sync.  I've turned on ADR for a bunch of my databases.  Maybe about 60...

You probably lack the SPN's for SQL server.  You can check them with the Microsoft tool:  https://www.microsoft.com/en-US/download/details.aspx?id=39046

The tool can even generate the commands to add the missing ones.

Maybe install the Kerberos diag tool and see if it checks out:  https://www.microsoft.com/en-US/download/details.aspx?id=39046

The SSPI error is usually associated with missing SPNs.