That is another unit (As you also can see from the Feldpostordnung).
Im not talking about the "SS-Begeleitbattalion" but about the "Ordnungspolizei-Begleitbattalion", confusing?
The only combat action OPo Batt. "Steiermark" saw in 1944-45 was a hunt for some sowjet parachute agents near the Hochwald HQ. They left Himmler on his order when he reached Dönitz HQ in Flensburg, shortly before he was captured.
Please excuse the smal size of the pictures.