Not sure how surge brakes could damage a hitch?
In theory, when you apply the brakes, the dolly momentum will push against the braking mechanism of the dolly, thus apply brakes to the dolly as you apply brakes to the towing vehicle. The harder you apply the brakes, the harder the brakes are applied by dolly to the dolly brakes. If everything is working proper on the dolly, and the tow vehicle, you should barely notice a dolly (or any type trailer w/surge brakes) whenever you apply the brakes in the towing vehicle.
1995 Bounder 35 UWB, F53