Not sure if your aware us this or not but I took a look into the Rare pokemon task glitch, the event turns on when the switch RarePokemon is turned on however you turned RarePokemon off before you the events was registered as complete. The event deleted it self before it register itself as complete.
Also I'm not sure but I think you used the wrong switch to register the event as complete.
Edit: Found a glitch, for the Fountains task you can fight the Carvanah again if you check the last fountain before heading back to the help center even if you caught/beat before.
Edit: Ok looked into that glitch, for the right fountain near the station that brings you to goldenwood you have it set so that the event completes when the switch hits 6 unlike the others which complete by turning on self switch b.