I am 100% certain about the cap of 60k miles per ticket. Many people have tried to press this issue with Marriott Rewards to no avail. I'm sure you can find many posts to that effect by using FT's search feature.
I suggest someone call back about the issue of whether the 106k point refund is for one cert or two. My information may be wrong, but since it comes from multiple sources, I think it is more likely that the rep KathyP spoke with was mistaken. If I'm wrong, I'm sorry. But if I'm right, it could be very profitable for some of you fortunate enough to have those big balances!