You may well be right. The nice thing about holding MON now is that I'm ok with either outcome. If the merger doesn't go through, the stock probably falls back in the short run, but I avert a huge tax hit and I think MON will do well as a standalone company over the next several years.
Nixing the DOW-DD merger will lessen the impetus for regulators to block the Bayer-MON merger based on the argument that there are simply too few large players in the ag-tech industry.
To the extent that the DOW-DD merger has passed muster with the EU (although it still needs clearance from the US and China, among other countries), the likelihood of the Bayer-MON deal being approved went up a little.