No, it is not possible for Ularu (also known as Uluru or Ayers Rock) in Australia to be part of the Moon formed by the collision between Earth and a small planet called Theia. The theory you mentioned, known as the Giant Impact Hypothesis, suggests that the Moon was created when a Mars-sized body, Theia, collided with the early Earth. This collision led to the ejection of debris from both bodies, which eventually coalesced to form the Moon.
Uluru, on the other hand, is a large sandstone rock formation located in central Australia. It is a terrestrial feature that has no connection to the Moon's formation. Uluru has been present on Earth for millions of years and has no relationship to celestial events like the collision that formed the Moon.