Can any VIP help me shed some light on this case please ??Thank you

So i am getting all my paper work ready to apply for PNP as the main appplicant and i have all the points that i need to obtain nomination.My main concern is with my spouse he was arrested in Feb 2001 in the US ,the charge was for aggravated assault but the official charges end up being for simple assault ,this was his only issue with the law and first offence also nothing else on his record ever since. Hopefully someone here with experience can tell me the options that i have.He was NOT convicted ,guilty plea was not adjudicated ( during deferral) and judgement was deferred and he received a 12 month probation which was completed in July 2002 ..i have his discharge papers from court where it says that all fine and probation were completed and that the discharge is NOT a conviction .Now for what i could understand the "committed act " only apply to pending charges or charges that weren't dealt with. And that if everything was dealt in court all that Canadian immigration care is if a conviction was entered.Will this be a problem for us ? and if i need rehabilitation for him will they go by aggravated assault ? or the official simple assault charges ? Weapon was involve but no one was hurt ,was more of threat thing which is why it was downgraded to simple assault and not assault with a weapon.What he got was kind of a deferred adjudication or deferred judgement i look everywhere online( canadavisa.com included )and most of the info i got is that these are not convictions for Canadian immigration but does the nature of the crime matter ? How should i handle this case with CIC when the time comes ? By the time i enter the federal part of my application it should already be 10 years since probation was done ,but i don't know if that even matter in our case . Please help i need to know if he will need rehabilitation or since he was not convicted he won't need it but has to disclose everything .Thank you ,God bless.