I have no doubt that Corbyn Labour will be looking for serious ethical and policy failures by both the Tories, and the Blairites within Labour, to differentiate from and attack or subdue them.
The issues with ME (and BPS & MUS more broadly) are an intersection of such failures across several policy fronts, all nicely rolled into one convenient package, that offers Corbyn Labour a nice big policy club to wield against their political enemies.
No idea what Corbyn's views on this issue are, or if he has any, or if he is even interested. But given his general stances and comments he would seem more likely to be more sympathetic to our plight than any political leader in the UK over the last 30 years.
Also have no doubt that, given Corbyn has a good chance of being PM before much longer (best I can tell), the PACErs and friends will be trying extra hard to win Corbyn Labour over. So anybody with connections to senior Labour needs to get talking to them and make sure we get to put our side of the story before they make a rash policy commitment they can't easily back down from. No politician wants to be caught in that situation.
We don't need uncritical support from Corbyn Labour. We just need to get them to understand that all may not be as the UK medical establishment claim, that this has important implications beyond just one disease, and that consulting widely (including outside of the UK) is a wise move before finalising policy on this matter.