few things to know here

1) Marriott has recently moved most of their sales team to regional sales offices - this gives the freedom to the sale managers to handle a clients needs anywhere in the world however it also has some drawbacks (the jury is still out as it just recently completed it's rollout - the rest of the industry is watching closely)

2) Hotels have tons of history of various types of groups and offer room blocks according to this history which is why they are offering only 10 rooms, typically if you need more than 10 the hotel will be willing to offer them but they are trying to prevent holding a large number of having only a few of them "picked up" (used)

Now with the above said you have every right to expect a personal telephone call to discuss your needs - unfortunately this didn't happen (even with the new system it's suppose to happen), I'd reach out and express your displeasure at the initial contacts you've had