I don't know who organised the strike teams for Mt Bold, but generally speaking, an IMT would request a certain number of strike teams. The request would be sent to the Region, who action that request - so it would generally be who arrange the strike teams.
Having said that, I have been at fires where Region has
arranged several strike teams to respond to an incident, without the request of the IMT / Incident Controller, and the Incident Controller had no idea they were coming, until they went screaming past the fire station, lights & sirens, going to call.... thing was, fire was under control, no more resources required, and it had just started to rain....
Pip