Don’t know the guy, so I will leave it to God to judge the authenticity of any professed faith. I do know that if he thinks Aslan has anything to do with Mohammed or Budda, he doesn’t understand the story of Narnia nor C.S. Lewis.
Someone should give Neeson a copy of CS Lewis’ book “The Problem of Pain”.
Lewis wrote it as a suffering widower searching for answers from a Christian perspective, and Neeson might appreciate more about CS Lewis and Christianity if he read it.