I'm not saying he held a grudge ever since...
He also wasn't angry at Roglic, but at the motor in front of him. And Dumoulin tended to be angry quite often when he simply wasn't good enough.
I think Dumoulin was a good guy who simply didn't enjoy his job in the last few years of his career.
We know Roglič liked & respected him, i.e. on a spectrum between Bahrain & a no risk no glory suicide descent (basically that's Rogla's 1 to 10 personal gauge between his most hated & most loved things), Dumoulin was probably a solid 7.