Again, 'discard from play' does not care where the card ends up. You play the action on
Just a Nuisance and he
leaves play (discarded.)
By default the card hits the discard pile because it was discarded. Alternatively, it could land on
Earthborn because it was discarded.
Either way it was discarded.
Where the card ends up is in essence more an effect [of the discard] than a cost. Pippin's effect will resolve as normal regardless of where he's discarded to.
discardThe default meaning of the word "discard" is
"discard from play." Discarding from other
locations (such as from your hand or from the
top of your draw deck) is always specified.
Cards are discarded one at a time so all players
can see which cards are being discarded.
When you discard a companion or ally to use
its game text or as a result of some other effect,
place that card in your discard pile (not your
dead pile).As shown, the definition itself has a "when you" trigger followed by an effect.
Bib, I had followed your logic for years, "You know this to be true..."