Because this is wrestling, I would not bet against Lawler wrestling at some point again, but if there is one 'legend' type who wouldn't, it would be him.
Old wrestlers keep going primarily for two reasons. One, they need the money (Ric Flair, Hulk Hogan, any number of 80's stars working your local VFW Hall this weekend), or two, they need the adrenaline rush of hearing a crowd pop and they love the business (Terry Funk).
Lawler certainly does not need the money. Multi millionaire many times over, and wealthy before he ever took a check from Vince McMahon. Makes a shit ton of money to announce matches, and because he's been doing it for 20 years, he gets residuals from nearly every single DVD that the WWE has ever produced.
As for #2, Lawler has always taken indie bookings, but he is not somebody who grew up as a fan and has any sort of love for wrestling. He fell into the business, and always saw it as just that - business. When people ask him about old classic Memphis angles and matches, he barely remembers any of that stuff, because to him it was just make your money and move on to the next angle. He touched on that in his book about ten years ago. He never thought about any of the matches he had in a historical sense, he just sees wrestling as a means to make money and nothing more. He made no effort to hold on to memories of things like that. Wrestling "purists" hated the Memphis territory in his day for the silly angles and characters, and repetitive stories (monster heel kills jobbers, beats Lawler for title, Lawler wins it back in the rematch at the sold out Mid South Colosseum, bring in new monster heel, rinse repeat). He's not a guy who thinks wrestling is anything more that business.
I get the sense that if he feels like wrestling is dangerous, he won't do it. He doesn't need the money, and I don't think he particularly cares about nostalgia pops or keeping his legacy alive or wrestling because he loves to do it. I could be wrong, it's just the feel I get from him.