G = k T
Where G represents Einstein's tensor and T represents electromagnetic origin of the mass.
These are just the standard Einstein equations, without the cosmological constant. They have not in any way been amended.
The main difference is that the former equations refer to neutral bodies while the latter equations represent bodies with electric and magnetic moments.
No, that is incorrect. The first equation is the
exterior vacuum equation, i.e. the equations for outside a mass/energy distribution. It yields vacuum solutions such as the Schwarzschild metric, the Kerr metric etc etc. The second equation ( with SEM tensor present ) yields
interior solutions, i.e. solution valid inside matter/energy fields, like for example the interior SM metric.
I am surprised that, since you come on here making such bold claims, you seem oblivious of even such basic facts.
By contrast, the T tensor in Einstein-Santilli equations is such that T_{00} is that the volume integral of T_{00} represents the entire gravitational mass of the body considered.
Again, this is just the same as in standard GR. The tensor element

is the energy density of a given system, so obviously the total energy of the gravitational source is just the integral over all of space-time :
In conclusion, the most important aspect, is the extremely large difference in numerical values for the source tensor that constitutes the fundamental novelty to such an extent that conventional Schwarzchild and other metrics are not even approximate solutions.
This is complete nonsense, since, as I have shown you above, there is absolutely no difference between the formalism you presented and standard GR. Furthermore, the SM metric is experimentally well verified within its domain of applicability, so there are
no "extremely large differences in numerical values". Refer here for a small list of empirical tests, many of which are based on the ubiquitous SM metric :
Modern Tests of Relativity
However the open issue is to see whether such a large source tensor is confirmed in nature or not.
See above.
This is the whole point because absolutely standard electromagnetism predicts that masses of all bodies no matter how big they are, are of purely electromagnetic origin.
Standard EM predicts no such thing. Classic electrodynamics deals only with EM fields and their sources, and makes no statements as to mass. Standard QED deals purely with the interaction between EM fields in general and light in particular with matter. Again, it makes no predictions as to masses, and it certainly does not state that all masses are of EM origin.
In his '74 paper, he completely dismisses the unification of gravitation and electromagnetism on various grounds and replaces it instead with 100% identification of gravity with electromagnetism.
How can he dismiss something that has not even been formulated yet ? Also, gravity is not an electromagnetic phenomenon, these two forces are of a fundamentally different nature - which is quite obvious, since the source terms of EM fields are 1-forms, whereas gravitational potentials are 2-forms. That obviously yields completely different physics.
For example, you need a special metric which is not the Schwarzchild
Again, completely wrong. Deflection of light is very easily derived via the Schwarzschild metric, and in complete agreement to observational data.
Also note that the electromagnetic origin of the mass provides a dramatic disproof of the GR representation of the bending of light because all metrics are no longer exact solutions.
Yet they give the correct values, which are in agreement with empirical evidence. Can you explain that ?