2010 LLT V6 no start fuel issues :(

[OnionBilly]

Just picked this 2010 RS this past December, only been driving it for like 3 and a half months- Love the thing but currently hitting a wall.

The car would get the CEL every few days for a day or two at a time then it would go away or come back a day or two after clearing it. It always was these
P0420
P0089


Searching around made me think I dont have to worry to much about this til emissions rolls around which wont be for a while.

Driving to ihop with the lady she started misfiring(car not the lady) which gradually got worse over the next few minutes. Was stuck in traffic at the time so I limped it to the parking lot which by then must've been running on 3 cylinders. I saw lighter colored smoke coming out of the back at some point and it reeked of gas/sulfur. She started once but very poorly immediately after it parked, and then after a half hour when we were done eating it wouldn't start at all(didn't have reader on me unfortunately).
Had the car towed to home where it pulled these codes
P0420 - Catalyst system efficiency Below threshold bank 1
P0300 - Random/multiple misfire detected
P0302 - Cylinder 2 misfire detected
P0089 - Fuel pressure regulator A performance
P0300 - Random/multiple cylinder misfire detected
P0302 - Cylinder 2 misfire detected
P0089 - fuel pressure regulator A performance
P0304 - cylinder 4 misfire detected
P014A - 02 sensor delayed response - Rich to lean bank 3 sensor 2
P0306 - Cylinder 6 misfire detected
P0420 - Catalyst system efficiency below threshold bank 1
P0089 - Fuel pressure regulator A performance
P0300 - random/multiple misfire detected
P0302 - cylinder 2 misfire detected

I was terrified because its a 3.6 that it was the timing chain. I had a replacement one Id been sitting on putting in, so I pulled it all apart and thankfully found the chains in good condition so I know it wasnt timing related. I threw the new timing chains on (following the procedure and video step by step) and am confident I put it back together correctly.

I changed the fuel injection pressure sensor on the 2 4 6 side fuel rail and have a brass sensor for near the fuel tank that I have yet to put on as well as throw on a MACE engineering 25mm intake riser/insulator. Still no start, charged the battery a bit since it was low and still no start. It now throws these codes
P0420
P0122 Throttle/Pedal position sensor/Switch A circuit Low
P0223 Throttle/Pedal position sensor /Switch B Circuit High
P0300
P0302
P0193 Fuel Rail Pressure sensor circuit high bank 1
P0089
p0122 again
P0223 again
P0300
P0302
P0193 again
P0089
P0304
P014A 02 Sensor delayed response - Rich to lean bank 2 sensor 2
P0306
P0420
P0089
P0300
P0302

Im using my spare car in the meantime but Im burning all my free time trying to fix this and I could use some help if anyone else has run into this before.