Official rules won't be out until the contest opens. Until then, unless a Dev opts to opine, the following is just a WAG. But I would imagine it's a "one entry per person; one person per entry" type of thing. If you want to collaborate with your friends and then submit it under one of your accounts with a behind-the-scenes agreement, that is beyond Cryptic's scope of power.
I don't think you need to concern yourself with procuring a modeler. It mentions on the contest info page that some kinda tool or program is gonna go live on Dec. 9, more than likely to facilitate the participation of those artistically and technically disinclined.
I, too, was looking for a modeller, as I am but a lowly graphic and cartoon artist. But re-reading the contest info page is how I picked up on that bit about the alluded-to program.
I would love to try this, but I work for Dell who purchased Alienware. I am guessing this means I am disqualified from being able to enter or win.
Unless Alienware has zero involvement. Cryptic could have just bought two computers from their website and sent one to a local print shop to be painted. Then you would be eligible. From what I gathered from the email it's just Cryptic, CBS, and Intel employees that would be ineligible.