The annotation above ( Luke 22:32 ) is very explicit in describing when the Pope may not judicially err, even when he errs in his private capacity.
First off, scriptural commentary isn't infallible, so you have to take it with a grain of salt, especially when it is dealing with theological speculation, which is by definition, a guess.
Secondly, Vatican I, in defining the limits of infallibility of the pope, referred to Luke 22:32 a few lines before it issued it's dogmatic decree. So we cannot say any longer that +Bellarmine's opinion matters because Vatican I "settled the matter" and gave limits on Luke 22:32.