I never said that it would be safe for him to leave after the 38 days. Just that he should at least stay that long before risking a short vacation. If CIC were to contact him, it's more likely that they will do it while they are working on approving him as a sponsor (the part that takes on average 38 days). I do not know what CIC policy is on a PR who is sponsoring a spouse and happens to not be in Canada when they try to contact him. That is why I said he should call CIC and ask if it's ok for him to leave and for how long.
He can not start sponsorship from outside Canada because he is a PR and needs to be residing in Canada to sponsor.