No, it's not. The status quo practice of plea deals not only encourages false guilty pleas, it also encourages false testimony that confirms prosecution narratives against other people who do not plea guilty, because the extent and effect of cooperation with prosecution is often a factor in getting a plea deal and the sentence received in it.
(Now, it probably does more to encourage true guilty pleas and true incriminating testimony, and so in net probably makes justice more accurate than would otherwise be the case; but it toys the balance in favor of the prosecution for both the innocent and the guilty to do that, which can be seen as violating the principle that protecting against wrongful convictions is off greater priority than assuring the guilty are convicted.)
But innocent party A can't choose not to have a third-party B take a plea deal in which testimony that reinforces the prosecution of A is rewarded with a lighter sentence for B than a guilty plea without such testimony would get.