If the original data set name is no longer treated as SMS by ACS, a RESTORE DSN=dsname without NEWNAME and VOLUME parameter will try to restore the data set to the original SMS-managed volume and the allocation will fail an SVC 99 error S99ERRCD => 9700 and message -
DATA SET ALLOCATION REQUEST FAILED - DATA SET orig.dsn IS NOT ELIGIBLE FOR ALLOCATION ON SMS-MANAGED VOLUME smsvol
In this rare case, you do not need the NEWNAME parameter, as the original data set name is no longer treated as SMS by ACS.
That means for the above sample -
will work and restore the data set as non-SMS on the non-sms managed volume NSMS01.