I'm sure you aren't doing anything wrong. Differences in pricing is usually attributed to group space purchased by a travel agency. It's likely that the dates you are looking at the agencies did not buy space for that particular cruise.
Your biggest difference is any rebates or credits that the agencies are going to offer you (which booking directly with Disney you will not get.)
Don't you get a rebate after your trip (ie. credits)-so you still have to pay all in full then refund you later right?
I wonder why they just don't take it off your price-it would definitely make some quotes look better.
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