A high French officer that died in that campaign is buried in the church of the city I live near. There's even a gravestone caved in the middle of a small church plaza.
1799 was a confusing time. In short, we were fed up with everybody invading our country, and we had realized by now that the French brought no improvement. I'm not surprised some people deserted, but their news that the entire regiment was considering deserting might be overestimated. At worse, they all wanted to stop fighting. At the other hand, the hussars had plenty of 'orangists' in it, so it isn't totally unlikely.
the 1799 campaign was a DISASTER for the Dutch (or batavian) army. And the navy..., God, they deserted to the Prince(William I) en masse. They (the captains) were actually told the ships would be considered an Dutch navy under command of the Prince - But they simply became prices of war anyway. I'm convinced we'd been butchered if the French hadn't come along. Not that I'm that knowledgeable on it anyway. I only know that when we were finally winning, we let them all go.