We have a post on how Alaska Miles can be a cheap way to redeem flights from Asia.
It makes sense to be part of Alaska’s programme to take advantage of those flights. In addition, I sometimes fly on Alaskan flights and so having status in their programme would occasionally be helpful. I recently contacted Alaska Airlines to ask whether they would status match my Marco Polo membership.
They responded that they did not match members who lived outside of Alaska Airlines routes and do not match Cathay status.
Alaska actually lists on its website the airlines whose programme status it may match. The list is here and does not include Cathay. I also cannot see any reports of success on the helpful Status Matcher website or in this Flyertalk thread.
So overall it seems clear that Alaska will not match Marco Polo status.