Think of it this way: you can't play
Pathfinder if you can't spot a ranger. It doesn't specify "To play, spot a ranger", but "Spot a ranger
to" tells you that spotting a ranger is part of the cost of playing the card. You have to meet the costs otherwise you can't play it. Exactly the same case here.
And you have to play the event (and therefore have to be
able to play the event) in order to remove
![1 [1]](https://lotrtcgdb.com/forums/Smileys/classic/1.png)
and put in on the bottom, because the card says so.
Thranduil