A theory must meet two criteria: 1) it must be self-consistent and 2) it must be compatible with known experimental facts. The notion that Einstein's theory is a gauge invariant theory doe not meet both.

If you read Zhou's paper [1, 2] you will know that Einstein's equivalence principle implies that the covariance principle is invalid. In my paper [3-6], I show this explicitly.

There are many so-called scientists who are more suitable to write stories. In other words, there are many crackpots in theoretical physics. You are quoting one of them.

References
1. Zhou Pei-Yuan, “On Coordinates and Coordinate Transxxxxation in Einstein’s Theory of Gravitation” in Proc. of the Third Marcel Grossmann Meetings on Gen. Relativ. ed. Hu Ning, Sci. Press & North Holland. (1983), 1-20.
2. P. Y. Zhou (Chou), “Further Experiments to Test Einstein’s Theory of Gravitation” in Proc. of the International Symposium on Experimental Gravitational Physics, Guang Zhou, China August 1987.
3. C. Y. Lo, Space Contractions, Local Light Speeds, and the Question of Gauge in General Relativity, Chinese J. of Phys. (Taipei), 41 (4), 233-343 (August 2003).
4. C. Y. Lo, The Bending of Light Ray and Unphysical Solutions in General Relativity, Chin. Phys. (Beijing), 13 (2), 159-167 (February 2004).
5. C. Y. Lo, The Principle of General Relativity, the Restriction to Covariance, and Stanford’s Experiment Gravity Probe-B, Phys. Essays 18 (1), 112-124 (March 2005).
6. C. Y. Lo, Misunderstandings Related to Einstein’s Principle of Equivalence, and Einstein’s Theoretical Errors on Measure-ments, Phys. Essays 18 (4), 547-560 (December, 2005).