Talk about clutching at straws. The referendum was not fought on party lines and MPs were free to campaign with whichever campaign group they desired. Kate Hoey chose Grassroots Out, a group supported by the likes of Tories Peter Bone and Liam Fox, George Galloway and, of course, Nigel Farage (then of UKIP). She later expressed support for Leave Means Leave, a group set up after the referendum to campaign for the Leave mandate to be implemented. Again, this was a non-partisan cross-party group, a fact pointed out by Hoey in the following tweet.
These outlandish and unfounded calls to expel Kate Hoey are just more sour grapes, albeit with a long-term Brexit-blocking purpose in mind.