As Rivets was saying
The two trigger wires at the base of the solenoid should be a power & a ground wire.
If not the solenoid can not close to energise the starter motor.
One or both of trigger wires can be switched depending upon which particular Mx5060 you have.
The other big question is does yours have the electric brake module ?
These are prone to failure & a failed brake module will prevent the starter turning
So pull the trigger wires off the solenoid and jump the terminals, one to battery & the other to ground
Starter spins = faulty wiring
measure the voltage / continuity on both of the trigger wires, disconnected from the solenoid
with the key in the start position one should show volts & the other ground
View attachment 56720
From the diagram above note than the - ( ground ) connection for the solenoid trigger wire is done via the Brake Actuator ( terminal 6 ) and for that to happen the actuator must get voltage on terminals 2,4,8,1, 7 & 11 which only happens when the respective switches are closed