So I hope that what OP sent the Lurker makes more sense than anything posted on here. I can understand why Marriott can't fix this, it's impossible to figure out from what OP is saying.
Did you cancel the stay in time to get the points credited back? (That's a little unclear)
And how does the second stay even enter into this.
If you bounced around like this on the phone it's probably hard to figure this out.
I agree with an earlier poster Break this into two issues and quit merging it into one your making it too hard to follow.
Unlike others on here, my experience with Marriott customer service has not changed recently and I have found them very helpful.