you can drive back with valid I-94. Just take the H-1 Approval notice with you. They will check.
We were back from Canada 2 weeks ago. My hu*****and and I are both H-1. My hu*****and got I-140 approved 2 years ago but didn't submit 485 yet, same case as yours. Our daughter has US passport though, we feel but not sure if that helped.
Don't go to apply the visa if you don't have to. If you got denied, you won't be able to come back.