Like I already said, if they asked for his passport already and did not mention it, it sounds like you got away with it.
PR sponsors must be residing in Canada. You may say you were only visiting but 3.5 months is quite a long stay. I would generally advise PR sponsors not to leave Canada for more than 3-4 weeks at a time and if that, make sure that someone is checking their mail and messages in case immigration were to get in touch. If immigration had found out that you were gone that long, they might have stated that you were obviously not living in Canada any more and they could have cancelled your application. It has happened to other people but it sounds like you got lucky and they did not find out.