Sorry to hear of your extreme damage and danger from the nasty high speed failure of the parking brake..
I also own a 2001 30' LY30 Airstream Land Yacht. It was Marketed as a Low Profile Class A Motorhome or Coach. Height is only 10'6" to top of AC's. It Goes Anywhere.
I have taken this Boondocking for 10 years all over the Northeast. Especially in the Deep Woods and Mountains of Maine, NH, VT NY. Just explored Western Virginia for 27 nites this July 2020 from MA.
I love this unit and now tow along a 2800lb 2003 Chev Tracker ZR2 using a Blue Ox Tow Bar.
The P32 Parking brake is the most common repeat offender with failures. Sorry, It is too late to warn you that when the yellow warning light is illuminated, The fluid pressure Holding the brake Open has dropped below the 1400 psi level triggering the rear sensor's Light. This is either the Rear Evil Grey sensor Leaking on the ground from the actuator below the rear of the Transmission, or the Front Evil Green sensor on the Parker Pump leaking up in front of driver.
The Parking Light is meant to be on Only when you are in Park or have Pulled the Yellow Handle while stopped. Either one or both sensors will Fail every couple of years.
When the Light Comes on you usually have a little time before the brake starts to drag. Still, The driver must notice and pull over to stop.
I carry 2 new sensors of each as spares and a gallon of ATF fluid. It is easy to get Rolling Again by removing a Single 10mm Bolt with Nut joining two flat linkage arms below. (WH In Manual)
I finally replaced Both of these GM parts with the Special Custom Parts Kit from Brazel's RV which are industrial rated and unlikely to Fail through Leaking. https://www.brazelsrv.com/
There are many threads on this subject.
Happy to share my self service info.
Send me a private message if you want to connect.