I think it would be odd for a mere captain to be at the board meeting, seated right across from an allegiant general. And I think Hux has plenty of motivation from 7 and 8 to hate Kylo (not that he even liked him in the first place).
I had this thought as well. The board meeting is supposed to be comprised of executive officers. But I suppose Hux could be forced to tag along on these meetings. As in, he’s a captain in name only.