If he can withstand another credit pull, the best option is probably signing up for two Citi AAdvantage cards on the same day. That's 100k miles, enough to book first class for both of you.

AA will offer you mixed AA and HA redemptions to get you to Hawaii. You can search on their website for your dates to see some examples.

You can save the Hawaiian miles for later or use them for interisland flights.

Although, to answer the question you ACTUALLY asked... Starwood points transfer to HA miles 1:1 and if you transfer 20k you get a 5k bonus. The current signup offer for the card is 30k after $5000 spend.

So, if you got the SPG card and spent $5000, you'd have 35000 SPG points, which would transfer to Hawaiian as exactly 40000 miles.