Legally, it would be tricky, as a person cannot be tried for the same circumstances with the charges reframed. The exception would be if there was new evidence, not known of as of the time of the original trial, that Rudy was the sole perp, or perp with other unknown perps.
The only option, if it is really so "there is insufficient evidence" or even "evidence" in bad faith, would be to annul Rudy's conviction.
For example, say we charge Macca as being one of the four Beatles, the others being, Lennon, Ringo and George.
If a court declares Lennon, Ringo and George to be legally, non-Beatles, it means neither is Macca.
Say it decides the other three Beatles were Mick, Justin and Angus. It makes calling Macca a Beatle unsafe.
So you see the problem.