Ontario has intranasal benzos for ACPs. Midazolam stops the majority of seizures. If you can't get a line on site before you move the patient, and it's pretty critical, you don't wait. As you can give it without an IV, it's not the need an IV for pain meds is, though Ontario has gone back to morphine from fentanyl and morphine can be give rectally if needed.. though personally I'd prefer to not need to try, lol.
With my preceptor, we'd be on route with a critical patient, we'd pull out everything needed prep, look for the best vein, and possibly slow to a stop if a light was red and hang on for a second to see if we could get it. One shot, see what you could accomplish.