God may lead people to be Catholic or Luthern or non-denominational as a stepping-stone to becoming LDS. This would be akin to Lehi's family being led to Bountiful before crossing the Ocean to the "Promised Land". The LDS Church is the Promised Land and the only train that will gets its people safely to Zion.
Yes, the LDS Church has not yet arrived at our final destination; but it is the only train, boat, vehicle that will get us there. Any other thinking that a person can get to Zion outside the LDS Church priesthood authority is tragically mistaken.