So, to say that Topp is likely to "go Hazen Argue," you must mean that whoever eventually wins (or the staff of the eventual winner) will inevitably freeze Topp out of any leading role in the front or back rooms of the party.
I think to "go Hazen Argue" would just mean to switch parties after having run for the leadership; though, there is not a single candidate who has been seriously talked about for the leadership who I think would do that.