The 1.7 milliseconds is the one which scares me. The DA-40 I fly presumably has the same FADECs with the same problems. What's the time required for a relay (or two relays in series) to switch? Because on the DA-40 you've got the ECU backup battery, but it requires at least one relay to switch (maybe even two, I do not have the POH to hand at this moment) to activate after a main bus failure.
Although I'd be very surprised if extending this time to the 50 milliseconds mentioned would help in the case we're discussing here.
AFAIK, the gear doesn't come up in less than 50 milliseconds...
B2N2, does the gear motor also draw 30 amps when *lowering* the gear?