Hello John,
I don't see a probem doing that please make sure the following is in place (Try this on only one DMP before sending the upgrade to multiple DMPS) :
1) Register the DMP to the DMM, Make sure the DMP shows up as green for more than 15 minutes from the time of registration.
2) Try polling for the STATUS of the DMP, Select this DMP --> Click "Run Task" --> Select "System Tasks" --> Select "Status". If the STATUS returns with bunch of MIB values and a page long output, That indicates that the DMM and DMP are communicating properly.
Technically in this case, the DMM is just acting as a WebServer and pushing out the firmware file on the DMP.
Let us know how it goes.
Thanks,
Sagar Dhanrale