It sounds like you solved your problem, but I just wanted to point this out...
But herein lies the rub: I spoke with my mortgage broker and he said if I got the Jeep now, I would "crush" (his word) any chances of getting a mortgage.
That's true. So let's just flag this for future readers: if you're buying a house, DO NOT make any major purchases on credit while you're waiting to close. Wait until AFTER you close, because yes, it's true, it will temporarily lower your credit and that could make your mortgage deal shrivel up and die before your eyes. Many lenders do check your credit again right before closing, and if you've bought something--or missed a bill payment, or otherwise lowered your credit--your deal may fall apart.
Whereas if you wait until after you close, preferably a month or more after, your new mortgage will show up on your credit and will BOOST your credit (lenders like people who own their own homes), thereby making it easier and/or cheaper to buy the new thing on credit.