GG --
My long history with Hilton is not quite as long as yours, but I rarely stayed at the brand because of the 500 point cap for non-business stays; mostly I stayed at Marriotts.
My newfound conversion is due to the fact that both programs are now on essentially equal terms as to point earning capability at different brands of properties and rates.
However, for me, Hilton now surpasses Marriott in a number of ways that I have discussed in many posts, before.
I would ask you to again try Doubletree. My wife and I stayed there on her way to the Conquest promotion, and she had her points posted within 3 days!!
Just be sure to remind the fron desk clerk continually about your point earnings and you MIGHT have better luck!
No sympathies needed re Marriott -- I am perfectly content with Hilton and its family!