FOLLOW UP ;
Guys, at the same time I reached out in this blog, I also emailed the USGA , explanation, question and pics. Much to my surprise, I received a quick reply. Basically, they sort of rode the fence IMO. They mentioned it was okay for recreational use, but that unless Model Local Rule G-2 was declared in a higher competition ( the groove rule of 2010 ) , it would be still be okay, but non conforming if that rule was declared. I even had two rules officials look at the reply and they agreed it was cloudy at best. Honestly, it was too cloudy of an interpetation for me. I don't care if I'm paying my buddies in rec golf or playing competitive golf , I want ALL my clubs legit , no question. I'd had the club for a long time, just bought it out of storage and it was magic on the course. But I wanted to know it's legality. It' is not by my understanding and a new Vokey 56* is on the way.

I think you answered your own question. Depending on the rules the day of competition, it may or may not be legal. The groves on a wedge over a quarter of a century old can’t be in prime condition. As the rules have changed, the balls and wedges have been tweaked for better performance.
For special events, I prep with the ball and clubs I plan to use. Might as well to commit to equipment approved under any circumstance and dial it in.

You are correct, if you want fully conforming, use newer. The rules exception they referenced exists because there are so many old ones out there and low level completion is likely not decided on a few spinning wedge shots. One could make the point that there are likely more non-conforming drivers out there in play that have greater impact to scoring. If the USGA/PGA are testing and taking drivers out of pros hands every few weeks, how many amateurs have 3 or 4 year old drivers where the faces are worn into non-conforming condition? We will never know because that type of testing is not done at local or even state level competitions. Something to think about.