In terms of the amendment as it's written, it's broad in terms of how it would exempt the railway entirely from any insurance requirements, so it wouldn't be in keeping with the objective of the bill.
My other comment is that there are specific circumstances that various railways have, but this is based on an assessment of risk and what goods they actually carry. That's how their insurance requirements would be determined.
The railway you're referring to does carry a level of dangerous goods that would require that insurance and operates through the City of Windsor level crossings, so it does carry some element of risk with respect to its goods. But there is a regulatory authority that it could be adjusted given changing circumstances or to account for specific issues that might arise over time.