Have you tried to use one of the phone apps along with your scantool dongle, e.g. Canion ? They have worked out all the communications.
Since several of the commands to initiate are being sent and received properly, then there may be some issue with the final request sent--but i don't know enough about the protocol the help troubleshoot it. Almost everyone uses an app to access the data, very few try at the modem level.
Good luck let us know how you do with this.