Uhh what? Destroying the wall was very much ALL wrong
The wolf riders MIGHT be able to jump it. MIGHT, since the walls are 6 or 7 and the wolfs can jump 6. It's RIGHT at the top of their range, so could they really jump it? Put some spikes on it and even if they could, they'd only impale themselves, since they wouldn't be able to clear the wall AND spikes. Or make some barricades WITH spikes on the wall, problem solved!
Also, they don't ONLY have to worry about the wolf riders, right? The normal orcs could flood through the hole, even if the riders could've jumped?