Train puzzle glitch.

Hi, we cannot do the train line puzzle as there isn't enough pieces. After trying everything we looked at the guide, it cannot be done as there is one vertical piece of track missing!!! Even the skip doesn't work on this puzzle so it seems we are stuffed. We don't really want to start the whole game again.

The missing piece of track is elsewhere.
Look in the electical panel box by grandfather's studio at top left.

Thank you. Sorted.