Has anyone here worked as a corner worker during a GP event, do they have any specific instruction in in an instance like this? OR if your directly in the impact zone, clear asap?
The first and foremost priority (redundant for a reason) is the safety of the rider that crashed, the riders still out on course and the safety crew/medical workers/corner workers.
Most likely, the marshals were not willing to help get his bike back on track because literally the vast majority of the pack was coming into and through that turn and to do so would have put Casey and the other riders in danger.
Fact is, the ONLY thing they are required to do is the clear the impact zone and verify the health of the rider and assess any medical needs. They help get riders back going usually out of simple kindness. They aren't required to help a rider get back on track.