Of course they are, as both claim to uniquely be the one true org, and both require unwarranted unquestioning implicit submission once you really get into it. Scientology however is far more insidious and crafty in ways of the world, effectively having a history as a religious mafia. But while the SO-CALLED JEHOVAH'S WITNESSES appeal to the common and even lower class of society, and uses Scripture and some Truth of it in order to give authority to its false interpretations of Scripture and history, Scientology much appeals to empty souls of certain successful persons, and uses some valid Scriptural principals to seduce such souls with its psychological manipulation and to fund its empire building.
Interpretation of The Word v space aliens ? Similar.?
Strong arm tactics v door to door ?
Buy your way to a planet, Galaxy or whatever the end goal is?
They may be classified as cults but that is the only similarity.
Almost all religions believe they are the only way.