I doubt that Caroline had much power in the dynamic between her and Logan. Perhaps she asked for the divorce and he decided to punish her by threatening to disown their children. They were probably married without a prenup, given the timing, although, wealthy families have been protecting their assets by legal agreements for forever.
As far as we know, while Caroline holds some shares of RoyCo, and Logan wanted her vote last season, she's been all but abandoned by the family. I mean, she was negotiating for Christmas visits last season. Apparently, she didn't have custody of that holida