Rebates are what they are, they come down from Chrysler, they aren't negotiable, and they're different for everyone depending on your situation. So, anyone that's quoting specific $10k+ amounts that you personally should be getting off is just speculating.
I have a few questions:
Why are you foregoing the rebate in lieu of a 2.9 rate? Typically, auto loans are lower than that today. You could keep the rebate and finance somewhere else, or use these other rates to negotiate a fair 2% rate through the dealer. Just go to the AAA site or any other major bank to get a rate quote and then use that as leverage. They want you to finance through them, they'll match the rate (unless you have bad credit).
What's the invoice price of the truck you want to purchase? You say the truck's MSRP is around $45-46k. Invoice is probably in the $41k area. Good deals are typically a few hundred under invoice (most don't quality for EP). You can get the invoice price at many sites - try truecar.com. Discounts can get better under certain conditions - like buying last year's models (and taking an immediate value hit because of it), but you aren't in that situation when ordering a 2015.
Current rebates are available on the Ram website. What do they say for your situation? It looks like the CC 6'4" Outdoorsman is getting $2500 off right now including the $500 for truck month. Using history as our guide, these rebates will only get better in the coming months. There's nothing new about the Ram so they aren't going to start dropping the rebates.
Chrysler's policy on orders is to lock-in and honor the rebates at the time of order. If they get better, they'll give you that as well. This has nothing to do with the dealer. You can confirm this by heading over to ramtrucks.com and chatting with customer service. But like I mentioned rebates will most likely get better by the time your truck is delivers, so this is most likely a moot point.
I just went through this with my 2015 order.
Good luck with the order!