I have done three interviews so far in this game. Two of them were successful, one not. Things I have been asked about training included whether or not I passed first time or first series on tests, whether I had resits for ATPLs and what my average score was, and various other 'softer' questions about how I found the training experience, was it difficult etc. Not once have I been asked about hours during training, not once have I been asked ANYTHING about my PPL (aside from me mentioning it in questions about where I trained).
I don't think you can be disqualified from obtaining any rating based on performance when obtaining another. If someone was really struggling during the CPL and going well over hours I would question whether or not they might have the aptitude for an IR but differently people are better at different things. I personally found the IR easier than the CPL for whatever reason.