well that is hard to say because it depends on what fights they each make over the next two years??? Maybe the guy that takes the toughest fights, for instance, Ortiz looks like a beast imo and would have a fair chance to take any of those 3 out "if" any of those 3 step up and fight him. Maybe its will be Fury not because he is the worst but if we are to believe the lack of desire he has left for boxing, well unless its all a joke/hype job, if his training is suffering significantly he may not make it past Wladdy.
both fury v wlad and joshua v parker are in very losable fights this year wilder is fighting the 15th ranked american heavy and then povetkin i would guess so the odds would be on fury /then joshua then wilder / but its entirely possible all 3 will lose before april of next year / which means healthy match ups.
This seems like the most likely scenario. Fury and his team don't seem to care who he fights, whereas Al Haymon and Eddie Hearns are notorious for protecting their hypejobs from serious opposition.