You can transfer Amex points to HA account for a slight fee and transfer HA miles between accounts for free but the account holder receiving miles must have a HA Visa credit card.

The transfers post almost instantly and can be checked online, just transfer the Amex points then book your flights.

I would book flights online yourself from one account, as mentioned below I did exactly what you're asking about quickly and with no problem.

BTW what airport and dates are you departing/returning and are you looking at First or Economy? Your questions about buying 3k miles from HA, booking and transferring miles, booking return etc. a bit confusing. With 170k+ sounds like a nice couple of FC RT awards to me that can all be arranged well in advance.....