Kayak came up with this, and Orbitz lets me book it (and it is significantly cheaper than via BKK), but I can't book on MH own site. I select Siem Reap as origin, and then type either Phuket or HKT in the destination, it doesn't auto-complete and blanks it out when I move away from the field.

Any reason for this? Is there no such published fare, and Orbitz constructing this out of separate fares? I am especially concerned as the connection is relatively short, 1h 10min, so if somehow this is not a valid fare and I miss the connection will I be stuck?

Thanks for any insights into this.