1) For the 1099 income do you have some kind of proof of income such as a paystub? Alternatively 3 months of bank statements will work (please tell me you deposit the money into a checking account before spending it)?
2) Call DCU and ask, but from what I know about the term LTV, yes 80% means you'll have to bring enough cash such that the loan amount is not more than 80% of the car's NADA Retail Value.
If you need a car ASAP, here's my advice. And I do agree that spending money on a car that is a bottomless pit is useless. Go to the dealer (negotiate the car price online first). They'll get you financed...but try to keep the rate lower than your DCU rate. Don't tell them about the 80% thing. Just I got approved for 8% from my CU, but I want less hassles and to go through you can you beat it. IMO they should be able to with no down payment required. If they can't beat 8% but come back with 10% or something, you can use a BS excuse like you've never really liked the customer support of the CU and just go with their financing anyways.
Then come home. Work on paying down the debt. In fact if you can, next month start by paying off the Cap One secured and JCP card if you can (other cards you pay only 1.5x min pmts)...really should pay 2x min to each card, but 1.5x works in a pinch. But after 1.5x min to each card, send the extra money you have that month with a focus on getting cards to 0 first. I know I usually recommend you pay off highest APR first, but having some cards report 0 will really help your FICO.
In a month or two, you'll hopefully be able to refi the loan as your FICO should go to 700+ if those cards get paid down. But one caveat: for refi you maybe underwater (ie owe more than car is worth). Look up NADA Clean Retail Value on the car...that's what lenders will use when refiing to see if you're underwater. There's a chance you'll have to come up with cash to refi if underwater, but if you're underwater by only 1k or 2k, you should be able to get through without any issue.
Try to bargain a good price on the car (over the internet)! Because the closer you can get out-the-door/financed price to NADA Clean Retail, the easier it'll be to refi 2-3 months down the road (and if it's lower than NADA Clean Retail, great...try to get it even lower 
). My tip: don't buy any extras like gap, life insr, warranty from the dealer...if you want gap, get it through your auto insurance provider. It's usually MUCH cheaper than the dealer. Here's my guide on how not to get ripped off when buying the car...I recommend you read it (you can skip the leasing section though):