2018 TOYOTA TACOMA Forward Collision Avoidance Warnings Problems

My 2018 Toyota Tacoma started showing a "forward collision detection system malfunction" "Contact your dealer" light came on that also indicates system is not on/functioning. I went to the dealer and was told the Millimeter Wave Radar Sensor Assembly #88210-04020 wad defective. My replacement cost and labor would be $1,543. I refused the service as I wanted to better understand the issue. I found that the exact item had fallen under a Toyota KOB recall. The same dealer had performed the recall in 2022. I believe the dealer should warranty the recalled part and service. It also appears the recall was performed incorrectly where a backing foam / seal that was to protect the sensor from moisture was installed incorrectly according to the recall recommendations.

Display a message in screen "Pre-Collision System Malfunction", lost power and start blinking light in cluster

While driving on 3 lane interstate, with the adaptive cruise control on, while passing a semi truck the front collision brake system activated. I was doing 72 miles an hour when it happened. The result was almost got rear-ended by another vehicle when my truck applied the brakes unexpectedly. The semi did not cross into my lane. My lane was clear. 0

I WAS INVOKED IN A FRONT END COLLISION MY BRAKES DIDN'T STOP FAST ENOUGH MY PEDAL WENT DOWN TO THE BOTTOM FLOOR AND MY TPS RADAR COLLISION WARNING DIDN'T ACTIVATE WHAT CAN I DO ?