2009 unfit Honda Fit

[DrivewayMech]

Admittedly, I am not a A/C guy. I've been building engines and doing drive train and electrical resto work for forty years as a hobby. As a favor to my daughter, I took on her friend's 2009 Honda Fit that blows hot. The blower moves a healthy amount of air and checks out. The compressor clutch relay checks out as well. I can actuate the clutch with my OBD2 tablet, but it will not otherwise engage. I suspect the pressure switch is protecting the compressor from the following fun stuff. Fun fact #1, it is evident that some clown up-ended a can of UV dyed PAG oil into the system. There is dye sprayed around the entire engine compartment radiating around the high pressure valve. Sure enough, I was able to connect my gauges to the high pressure side, but as soon as I tried opening the valve, it sprayed out UV dyed PAG oil everywhere. Fun fact #2, the low pressure side reads a little over 150lbs! I'm picturing an expansion valve stuck open. Although I cannot be certain, I suspect the UV dye also contained a sealant that's gumming everything in the system. Fun fact #3, I cannot obtain a high side pressure due to fun fact #1.
Question for the house: Is this a total system replacement or can I salvage some parts?

[JohnHere]

I presume that the 150 PSI reading you got on the low side is the static pressure (compressor not running). If so, the system now appears to be overcharged. What was the ambient temperature when you got that reading?

If sealer was put into the system, that's bad news, in part because if you take it to your local A/C shop to have them recover the refrigerant, they might refuse to do so.

Regardless, the first thing to do is to recover it and then install the proper amount of refrigerant into the system before any further testing is done. It probably had a leak to begin with.