The input of the TMSSPLIT must be a list of volsers and NOT a range of volumes.
We can use TMSGRW utility to generate a list of all active tapes using the following input:
//SYSIN DD *
CONTROL-SECTION
SORT VOLSER
ALTER INPUT=TMC
TITLE ' ACTIVE TAPES '
DEFINE DEL HX '02'
DEFINE SCR HX '04'
PROCESS-SECTION
WHEN FLAG1 ON SCR
REJECT
WHEN FLAG1 ON DEL
REJECT
WHEN VOLSER EQ VOLSER
LIST
REPORT-SECTION
PRINT VOLSER
PRINT DSN
PRINT EXPDT
The OUTPUT DD from TMSGRW can be used as input to TMSSPLIT.