Awning repair tape is good stuff. I think it should be up to the task. A length of Gorilla tape along the edge might be appropriate if only for your reassurance, too. Gorilla tape is a little like duck tape, but better.
Another alternative (that I've used) is to drive in a strong enough crosswind that the awning partly unfurls and the fabric gets sufficiently torn and worn and generally mutilated that the whole needs replacement. I'm not saying I recommend this alternative, just that I've used it, for better or worse....
