Any other part of the linkage that gets bent, may also cause a binding issue. As posted above, you have to check precisely. Close enough won't help here. Maybe you could narrow it down to a specific axle?
Did you remove the eccentric cranks on either side for maintenance or some other issue? Have they slipped?
Try taking those off one at a time and each drive connecting rod, one at a time until you find the culprit.
