FIrst, STOP and take time to understand how it works.

The "wing" is operated by the Body Control Module, based on information the Brake Controller provides. The four wheel speed sensors feed data to the Brake Controller and the Brake Controller tells the BCM what the vehicle speed is. Any issue with this data and the wing will default to UP because the BCM does not know for sure what speed you are traveling at.

Additionally, erratic DC power to the Brake Controller or BCM will also result in a deployed wing; it seems you have addressed this.

In cars that are convertibles, an erratic wing combined with a convertible top that won't move tell you that there is nothing wrong with either system and that the issue is in the Brake Controller or CLP/SSM (Central Locking Pump/Security System Module).

The various systems in the car interact with one another. THis may not be a "wing" issue at all.

Given what you have posted, I'd yank the CLP/SSM out of the cavity in the trunk area, pull it out of it's insulative blanket, and look for water intrusion or corrosion. Yank out EVERY electrical connector and look for dampness or corrosion. If you find any, toss the CLP/SSM in the trash, go find a used replacement, and get the last 2-3 feet of the wiring harness. Replace the CLP/SSM and the last 2-3 feet of wiring, including all connectors, and you should be OK.

If there is no water damage to the CLP/SSM, report back and we can go from there.