Also remember you can use Avios to book award seats on AS. I only pay attention to their flights from San Diego. I know that AS has nonstops to 4 of the islands from here.

"With the new Kona service, Alaska Airlines will fly nonstop to 16 cities from San Diego. The others are Boise; Boston; Fresno; Honolulu; Kahului (Maui), Hawaii; Lihue (Kauai), Hawaii; Los Cabos, Mexico; Mammoth Lakes, Calif.; Monterey, Calif.; Salt Lake City; Santa Rosa, Calif.; Seattle; Orlando, Portland, Ore.; and Puerto Vallarta, Mexico.

Alaska Airlines also has been expanding its presence in Hawaii this decade. In Kona, Alaska says it now offers 74 weekly, peak-season flights between Kona and Anchorage; Oakland; Portland, Ore; San Diego; San Jose, Calif.; and Seattle."

USA Today

You need to find seats for 20K when you search on the Alaska website. Then you call BA, because you cannot book AS online when you use Avios. It will be 12.5K Avios. I just looked at January for SAN-OGG. 25 days had 2 seats available at the low redemption level.

I believe that AS fly to Hawaii from San Diego, Oakland and San Jose. Where in the LA area do your parents live? Is a San Diego departure an option for them?