Agree. Emergency vehicles don't automatically get a "free pass", there are separate rules that apply an exemption. So the question and rule, as written, says that the emergency vehicles do violate the rule IMO. In the real world, there would just be other rules that would apply an exemption.

(IANAL, but have been driving emergency vehicles for 15 years).

I would say the tank is no longer a vehicle. More like a statue than a vehicle.

how is it getting into the park? If it's rolling, IMO it's still a vehicle. If a truck is dropping it off, still a no-no

What if the rule was created after the tank was already in the park? There was no information given on how the tank was transported to the park, and you're creating a violation based off a hypothetical.

Maybe a huge crane lifted it into the park from outside the park. Would the crane be in the park then?

What if it's fired from a cannon and lands in the park?

Are you being serious? Obviously the rule is not meant to outlaw that specific scenario and local authorities or the company that provides the transport will put measures in place to make sure it goes safe and sound; they will close the park, drive at walking speed, etc...

Not really an opinion if you follow the instructions, unless somehow you argue an ambulance is not a vehicle.