Does RQM 3.0.1.3 supports export/import of test cases to excel?

If you mean export RQM TestCase as rqms file and then import into Excel via ExcelImporter, then yes, 3013 should already has that feature. The main purpose is to import the manual script into Excel for offline execution then import the result back into RQM.

If you mean export TestCase view as a csv file, then no, v3.0.1.3 does not have that feature yet, it is from v4.0:
https://jazz.net/downloads/rational-quality-manager/releases/4.0?p=news#csv