I'd use the 1K number on the whole reservation. The EWR-IAH upgrade should be waitlisted as part of the IAH-HNL award and the status of that comes from the account the points were redeemed from, not the passenger. So even if you are listed as a 1K for the flights the upgrade is as a Platinum. And you get the best chance for the UA metal upgrades with the 1K number in there as well.