Regarding https://developer.here.com/documentation/fleet-telematics/dev_guide/topics/vehicle-types-and-measures.html
In case to utilize the REST API of Fleet Telematics API you can: calculate the route for emergency vehicle type also you can set comma separated list of types:
A comma separated list of vehicle types enables all permissions that
each of these vehicle types have.
But unfortunately, it is not possible calculate a route for emergency vehicle type using the FTCR route calculation because some of type of vehicles have been never implemented for FTCR route calculation, additionally mSDK 3.x is in maintenance mode that means it will be never developed new features for mSDK 3.x.
In mSDK 4.x - regarding this https://developer.here.com/documentation/android-sdk-navigate/4.7.6.0/dev_guide/topics/routing.html#get-routes unfortunately doesn't exist route options for emergency type, maybe it will be implemented later but road map is unknown.