It only shows 1 result per thread. If you searched within the PvP thread it would come up with many I’m sure.
Canishogun wasn’t an anniversary monster. However, it was in the 4th anniversary festival egg. It came out in May 2019. You can actually track when all monsters came out by searching for them in the tier list threads. It won’t give a perfectly accurate date, but close enough
I was very tempted too. Did 6 packs in the end and no Cynthia. I’d recommend saving for the anniversary because there will be other opportunities for Cynthia in the future