Looking for case law supporting blood draw without a warrant in a single vehicle accident where only the driver was injured. Anyone able to point any out?

Our Implied Consent statute bars it. See Transportation Code 724.013. Since this situation is not covered by 724.012 (b) (( what we call Mandatory Blood Draw)), the statute bars taking a sample without consent or a warrant. While you might well be able to argue exigent circumstance even after McNeely, you have a statutory bar. Sorry.

Unless the driver was unconscious and could therefore not refuse the draw, is that correct Clay?

100% correct, nice catch. That is why prosecution is a team sport.

Did the driver receive medical treatment at a hospital after the accident? Frequently hospitals will do a blood test in order to establish a baseline for treatment.