@Roberto_Marzialetti quick update: the getMetadata() NPE on a component restored with objectLoad( objectSave( cfc ) ) is fixed in 7.0.6.9-RC, which is out now: Lucee 7.0.6.9-RC available for testing.
The fix (PR #2840) and a regression test are merged into 7.0, tracked as LDEV-6490.
It would be great if you could try the RC with your setup and let us know if the error is gone, including whether redis.extension now works for you.