Welcome to TFP.
Your SUCTION and RETURN actuators are switched and plugged into the wrong sockets.
Open up your OMNI panel. Find where the actuators are plugged in. And reverse the plugs.
Freeze protection activates the spillway mode. Pool and spa modes activate both actuators, suction, and return. The spillway is supposed only to activate the return actuator. Since your freeze circuit is activating the suction actuator, this is an indicator that the valve actuators are plugged into the opposite sockets.
You can either open it up and switch their plugged sockets or physically swap the actuators between the suction and return valves. Swapping the sockets is a much easier method of changing the operation.
I will just be kind and say your builder does not understand automation systems.