The removing of the performance videos from the show youtube channel is pretty common practice after X amount of months, it's got something to do with image & copyright rights. Niall's performances are also gone. This specific case of deleting can't be blamed on Flopsy. Now, the difference with Louis is his team didn't upload the performances to his own personal channel like most artists teams do (see Harry uploading both SNL performances onto his channel) so THAT is on Flopsy & Louis' team.
Your last point is spot on