This is on my 2002 Corvette, 124k bone stock A4 except for Borla Cat Back system, bought it with 60k on it and it's mostly been used for long freeway commuting (90 miles a day)

I started getting an occasional check engine light that would go away after a while but it got worse and then I had an overheat because of a breach in the coolant tank, the temp went into the red but only for a few seconds because I pulled over right away and shut her down, engine did not go into protection mode, replaced the tank and all seemed good but the check engine light would come on more often and now would only go off if turned off manually via the Driver Information Center (code was P0300) finally got a scan tool on it and it stated P0305 misfire cyl #5, switched around plugs, wires & coil packs and injectors but still #5.

Did a compression test and found I have low compression on cylinder #5 (90psi vs 175psi for the others), a wet compression test showed only a 10psi jump and since the car overheated I figured I had a warped head or leaky gasket so I took the head in for a shave and a pressure test (valves and guides are good) and replaced the gaskets.
Got everything back together and same problem, 90 psi in cylinder #5, now the car won't pass smog
I'm getting the choo choo train puffing out the oil filler neck with the engine running so I'm getting some serious blow by (I replaced the PCV pipe)

Any input from you guys on this would really help I don't know if I'm at the stage for a new engine?
If so what am I looking at as far as replacement options? not looking to do crazy 500hp upgrades as the car is fun enough with the stock engine.
I don't know if it's the rings (I would think compression would be lower)
I tired cleaning the rings with X66P poured into the cylinder and left overnight, just in case it was carbon build up, no difference.
My guess is scored cylinder walls, I tried a can of Restore with no difference.

So I was reading up on "Eliminating Blow By" and all these Certech Gels results keep popping up, has anyone here had any luck with them?
$160.00 seems a lot for an engine treatment but at this stage it's a heck of a lot cheaper than an engine rebuild and all I want is the car to pass smog and give me a few more years as I now work from home and don't commute anymore so the car wouldn't be strained anywhere near as much as the past few years.