Unfortunately he suffered a debilitating car accident and the plans were scrapped.
One thing I do think needs to be clarified is that, by pretty much all accounts, it's not fair to blame Thompson's car accident for a Zeppelin reunion never happening. It was never really in the cards to begin with.
A lot has been said and written about it, but for the moment,
this is the easiest thing to hand:
The foursome arguably spent more time in a tiny club in a little English village than they did writing, rehearsing or recording. The good times quickly turned into a bit of mess – including a car crash and hospital stay for Thompson.
“Jonesy and I often chose to walk back to the place we were staying, at two in the morning. Pagey wouldn't come out, which is hardly the way to get everything back together again,” Plant recalled. “Meanwhile, Tony became a celebrity and was metaphorically earned around on everybody's shoulders. He ended up in one of these small mini-cars with five other people. They took a corner too fast and ended up in somebody's basement, went off the road, through some iron railings and down a few steps … . Tony was lying in the hospital going, ‘Oh, man, oh, man.’ So that was the end of him.”
And that was about the end of the sessions too. Page reportedly had tech issues, needing to replace the batteries in his wah-wah pedal constantly, and with no drummer, one of Plant’s roadies jumped in behind the kit. The group just wasn’t gelling.
With the Firm’s second album, Mean Business, already shipped and the band about to embark on a March tour, Page was short on time. And according to Jones’ account in Jimmy Page: Magus, Musician, Man: An Unauthorized Biography, Page and Plant were both short on desire.
“I don't know if Jimmy was quite into it, but it was good,” he said. “I suppose it came down to Robert wanting to pursue his solo career at the expense of anything else.” Jones hoped for more, as he told writer Mick Wall. “There’s definitely the feeling of unfinished business about the band," he said. "We had hoped to do to the '80s what we did to the '70s. I still very much regret that we never got that chance.”
Also, see
this interview with Robert Plant, some years later.
The bottom line seems to be that while Jones was keen on getting back together, Page was no more than diffident, Plant had little interest, and Thompson was turning out to be the wrong choice for a drummer. Plant and Page had grown too far apart at that point, and Plant was too interested in his solo career. (Indeed, he was about to record his most commercially successful solo album.)
In the mid-90's, of course, that changed - sort of - when Plant did those two albums with Page. But I think that worked because they were both in a different place by then, and not having their project fall under the enormous weight and expectations of a thing called LED ZEPPELIN made a big difference.
