The "forgiveness" WY ME is referring to is similar to being pardoned by their government. I looked into it years ago when I had a dui. At that time it cost 200, and the paperwork was mind-numbing. It included getting an FBI background search on yourself, which was a pain in the butt. On top of all that, there was no guarantee to get the pardon.
If I remember correctly we had 4 out of 5 guys in our crew stopped at an Alberta border crossing for DUI's and one 40 year old bar fight arrest. It took 3 days for their paperwork (pardons) to clear customs and and allow them to cross the border.
About 5 years ago I crossed the AB border with my family and no guns. They repeatedly kept asking me how many guns I owned. I told them it was none of their business (which it isn't), I was questioned some more, truck and boat searched, etc., but we we had done nothing wrong so they finally let us in.
In 1982 me and my brother were stopped at the AK/Yukon border crossing by an RCMP for lack of proof of insurance on his car. We even had his insurance agent call the border, and the local sheriff's dept from our hometown call the border customs to verify his car was insured. They refused to work with us until we had the AK state patrol in Tok confirm our story via a tele-type . Because of the delay we ended up having 100+ pounds of caribou meat spoil because we couldn't get our meat to a freezer in Whitehorse. In those days there were no cell phones, fax machines or internet to help us.
All you can do is do your best, tell the truth and cross your fingers when you cross the border.