Is it a continuation with the same flight number? I am flying ORD-IAD-LHR on the 15th, but on the same flight number. I have no doubt that I will get the DEQM on the whole itinerary.
Your situation is different.. even if you were not flying on the same flight number you would earn DEQM's because both flights depart on the 15th. The OP is crossing the date line on his transpac flight so his first flight departs the 15th and his 2nd one departs on the 16th. If it was one flight number all the way though yes I do believe it would qualify because it would post with a date of 6/15.. but that's not the case for the OP (probably).