Implausible to impossible. Whatever is around that star must be either changing its orbit, several objects in a far away orbit (They only've gone in between Kepler and the star once), or its a swarm of objects. The change in the IR radiation of the star is too irregular and at too irregular intervals to be a normal planet just orbiting it, and I'm honestly not sure how a living giga-structure could account for the weird signals we're receiving from this star. Plus, where would said plant get resources from?