Since the Y works, and the X doesn't, and the Z is connected a completely different place than the other two, I am certain they are not miswired. I have also tried to manually trigger the other end stops when moving Z or X, and nothing happens. I'll check the grub screws because I*ve seen some slipping, but the end stops still should react when triggered manually.
Could it be a board problem even if one of the end stops work, or is it more likely that the two end stops are broken? I'll try and swap the connections to see, but wirh a recently broken finger it's been difficult to move around 15kg of printer :)
Thanks for all your answers so far!