The driver should be current regulated. The run time graphs I have seen have all been pretty flat.
Judging by Texas Ace’s Test with the xp-l2 given the 550 lumen output of the Zebralight, my guess is 3vf at 1.25 amps or slightly more.
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Djozz tested the XP-G3 photo red here.
He suggested the sweet spot to be around 2 amps, its in that thread two post down from the linked post.
If the driver is current regulated, then it should work.
But if its not then I guess there is only one way to find out if it will survive. 