4.6L F150 VCT System Failure: Rough Idle, Low RPM, and Bank 1 Cam Phaser Malfunction

I've been struggling with a persistent rough idle issue on my 2007-2013 Ford F150 4.6L engine for several months. The initial repair involved replacing both timing chain guides, phasers, tensioners, and other mechanical components — the truck ran smoothly for a few weeks before the rough idle returned at low speeds. I took it back and had the oil pump replaced, which addressed the issue temporarily. However, after a few weeks, the problem reappeared. Since then, every major mechanical component has been replaced, yet the low RPM rough idle persists. After researching online forums, I discovered that replacing the VCT (Variable Cam Timing) system with a specific Ford part number resolved the issue for two months. However, the symptoms returned — now occurring intermittently, with the Check Engine Light (CEL) flashing on and off, and the idle becoming rough at times. Two days ago, the rough idle became constant. I replaced the VCT unit again, but there was no improvement. A visit to a Ford dealership revealed that the Bank 1 cam phaser is not functioning properly — all cylinders on Bank 1 are showing a 60 psi drop in pressure compared to normal levels. The VCT system is now outputting 0% actuation. The dealer has advised disassembling multiple components to check for scoring or wear on the cam caps, but I and several mechanics suspect an electrical issue — possibly related to wiring or cam solenoids. Any insights into potential root causes or diagnostic steps would be greatly appreciated? Are there known issues with VCT systems in 4.6L F15 or specific wiring harnesses that could cause intermittent failure?