I don't think so because the credits page of volume 6 states that the last chapter in that volume (chapter 57) was from the September 2019 issue and the credits page of volume 7 says the first chapter (chapter 61) was published in the October 2019 issue. If the three missing chapters were magazine only chapters then when were they published?
The chapter 61 uploaded by SSSSS/SteamedBunInvasion was originally numbered 58 but I asked the moderators to renumber them so they had the same chapter numbers as the volume releases.