@Lee VanRoss
I had to clean the dirt from my finger nails to find it but luck did prevail..
Looks like Sencor D F @ 0.5 to 1.0 lb per acre using non ionic surfactant @ 1 qt per acre.
I am in loess soil and it was fall applied. (Sept Oct)? Not sure if soil type is issue but check just in case,
While I did get a good kill I still had enough come through the winter that I chased strays the next year with a hand sprayer.
My problem came from a custom baler using a contaminated windrower and baler.
Since then I have become observant about requiring any custom machinery to be clean before pulling into the field,
There may be better products than what I used by now so talk to your chemical supplier.
Another tip, if you apply manure from any hay with mustard in it I would pile it for a year before I put it on a field.
Just to let you know how much of a pain in the (_ _ s) it can be!
Good Luck!