Throw and mow - FTW!
I'm not sure if those plants are really that tough, or if you failed to mix AMS with the gly, but you didn't get a good burn down...there's still a lot of green in that field. Also, it looks like you didn't mow and then wait for tender new growth before you sprayed. Done correctly, the method you used should have worked well enough to allow effective discing. As it is, you're getting close to seeing "thirt", which is ideal for food plots. You don't want to work dirt the way people have done it, traditionally...that's more than you need.
Broadcast a grain/legume mix, with maybe some radish and chicory, mow it tight, cultipack, and then pray for rain.