I remember that he did an Indycar race for Carl Haas's team when Mario was recovering from injury in 1985. That would also have been a good retirement activity with a better chance of winning, but he just did the season and a bit with the FORCE F1 team and no more. His reputation doesn't seem to have been tarnished by it, though. It must have just been a good financial deal.
A photo of Alan Jones in the Newman/Haas Lola at Road America in 1985 where he finished 3rd in his only Indy Car start. I was directly on the other side of the wall at the impact point at Station 6 during the Michigan 500 on lap 241 of 250 when Mario was injured. I can still recall the ground and wall shuddering from the massive impact and one of Mario's wheels flying overhead as my co-workers and I were ducked below the wall (then without catch fences). From eastern Pennsylvania's The Morning Call interview by Ted Meixell on October 16, 1985:
The most publicized setback was a horrible crash in the Michigan 500 on July 28, in which he suffered a broken collarbone and a hairline fracture of a hip. First, his injuries forced him to sit out a race for the first time in his 28-year career. Secondly, and perhaps more importantly, he had to race at far less than his physical peak - and with significant pain - in the four races that followed.
"I was at full strength for the first time at Laguna Seca (Oct. 6)," he said. "I was back to normal - there was no different padding in the car, I didn't need any assistance getting into or out of the car."
short Speedweek race recap and Mario's accident:
https://www.youtube....h?v=YQgX-7SRWtI
ten minute Road America recap showing Jones in Mario's car:
https://www.youtube....h?v=jbr3iYZa2m8