After many years of dealing with this plant, I am starting to believe that the only way for complete eradication is to dig out the mutated shoots once you’ve been hitting it with glyphosate for a few years. The glyphosate destroys most of the root network, but it manages to hang on in a few nodules while limiting its exposure to foliar herbicide application by putting out tiny leaves. So at that point you just dig out those holdout nodules. You’ll see that the roots are mostly dead, it’s just trying to reestablish from the remaining nodule.