Xenon Oxyfluorides

Xenon hexafluoride reacts with silica to form oxygen and xenon compound (X). The hybridisation and oxidation state of xenon in the compound:

Statement-1 : Xenon hexafluoride is kept in silica-lined vessel. Statement-2 : Xenon hexafluoride is not kept in silica-lined vessel.

Xenon hexafluoride react with silica to form a xenon compound (X). The oxidation state of Xe in (X) is

Xenon fluorides are all extermely strong

Xenon hexafluoride undergoes hydrolysis in strong alkaline medium:

What idea lead to the discovery of Xenon fluorides?