There will still be the question of how this sample occurred in a ditch on a side road beside a field that had never had that seed in it, and we may never know the answer to that. What you're now doing is confirming that what is in the field doesn't have GM traces. You've used large sample sizes over many years to confirm that there's no trace of any GM product still in the fields.
On June 20th, 2018. See this statement in context.