UZZ30 Wont rev past 5000rpm - Supercharged 1UZFE Haltech with Water Meth injection

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Hello to all the great members here at lextreme. I'm a new user and this is my first time posting and its also my first time ever reaching out for help (so know that I need it haha!.

We've spent so many countless hours on my dads UZZ30 1UZFE Soarer trying to fix an issue and hes at a stage where if I cant pin point the fault then its being parted out. Thing is I know how much he loves it so Im hopeful to resolve it! For context I've been building cars and engines for 8+ years and always fix it myself.

Any way heres the deal in hopes someone might have a suggestion.
1992 UZZ30 1UZFE V8 soarer. Has a 2.3 VMP Gen 2 supercharger. Haltech Sprint 500 ECU running off stock harness (which also has the 29 ECU still on it for the rest of the cars electrics. Water meth injection into intake pipe (pre-throttle plate). Stage 2 MV Automatics drag gearbox. External Turbosmart FPR. Walbro 460 in tank fuel pump. 550cc high impedence injectors. Usually runs 98 octane pump fuel but also E85 on occasions.

What happened: Car has been running mint with all of the above on it. Dads made different size pulleys for the charger (hes a fitter and turner)to test different boost levels and manifold temps. Thats all gone great. However one day he fitted the water meth injection nozzle in backwards accidentally and took it for 2 runs. Obviously it went epic and temps were super low however didnt know it was flooding the intake/charger etc with the water meth (it was gushing out). Still not knowing what he'd done he was on the 3rd run down the highway when he noticed the boost gauge reading 28+ (may have even been 38+) PSI which isn't possible with that pulley. It should have had no more than 10-12 PSI.He noticed and immediately backed off at which time the car practically died and barley made it home. Since then whenever revving the car it wont go past 4750RPM. Trying to drive it, the car hesitates in more than 4psi of boost and carries on. Intake temps go up dramatically too.

What we've done to fix the issue:
Noticed Cyl #1 comp was super low, so we fitted a replacement engine (yes drastic but cheaper than a set of rings and gaskets). This has all new sensors including the TPS.
We've adjusted the TPS to ensure its reading correctly.
We've checked the VAC lines to make sure water etc isnt in them. I also wired up an external MAP sensor for the haltech in case the meth fried the internal one (which a vac line went to).
Pulled apart the supercharger and all seems fine, spinning great and balance fine.
Disabled the water meth injector and setup, no change.
Had the injectors flow tested and ultra sonic cleaned.
Made sure that the FPR pressure continued to rise during the revs.
Had the car on the dyno and no matter how he set the tuning or increased/decreased fuel etc it still did the same thing and was knocking too (yikes!)
Tried flashing the haltech to stock firmware, then applying a stock base map, then applying the working tune.
Tried another working Stock UZZ30 #29 ECU just in case.
Replaced all busted plugs on the engine harness when we swapped the motor
New distributors, new spark plugs, new fuel filter.
Tried pining the bypass valve on the charger shut to ensure it wasnt leaking air out.
Different 02 sensors in the exhausts.
Coil on plug conversion then back to stock dizzy with leads.

If you've read this far then thank you for even taking the time to look at my post. As you can tell I'm quite stumped at this stage!
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Thanks for the reply! I haven't tested each signal wire no, but as far as I can tell each sensor is reporting correctly. Having said that although the injectors for example say they are at 40% or whatever I guess we can't guarantee the signal to each one is working correctly hey.
Checked the logs and monitored voltage during the issue and runs, never spiked or did anything stupid just 13.6v on average.
Fuel flow seems fine, the external fuel reg gauge on the return line says 40psi at idle and rises up to 60-70 under load.
In case it helps anyone we figured it out. The liquid meth washed all the grease out of the supercharger bearings. After rebuilding it things work mint again.
In case it helps anyone we figured it out. The liquid meth washed all the grease out of the supercharger bearings. After rebuilding it things work mint again.
Bullet Cars here in Aus. told me a while ago that you should repack the rear blower bearing with greece every 12 months if running water meth. Although I would never have linked the problem you described to dry bearings. Good to know. Thanks