I want to know if I can certify that the coldbackup can be used as a recovery

A status 1 on Unix/Linux backup is never good.

 ERR - Cannot open file .... Errno = 13: Permission denied

These files were not backed up due to insufficient read permissions.

We also cannot say if backup of Oracle databases were good and can be recovered because we do not know in what state Oracle was during the backup.

Best (and probably only) way to say for sure is to restore to a spare server and see if Oracle dba can start the database.

PS: Please reply to your other post as well:

https://www-secure.symantec.com/connect/forums/could-not-reset-access-time-oracleoragridgrid11gloghpescs1clientclsc3log-errno-1-operation-no