Is Einstein's article not original, but rather a secondary one to Poincaré's work? Was Henri Poincaré the factual creator of the Special Theory of Relativity? Is the situation even worse for Einstein? There are three explanations for the strange coincidences of June 1905. The first one is the traditional version: Einstein himself wrote his work without reading the works of Lorentz and Poincaré. The date-specific similarity between the publication of Einstein's work and the publication of Poincaré's works was a coincidence. The Göttingen conference had no connection with the discussed events. The second possibility is that Einstein got acquainted with the works of Poincaré and Lorentz and his work was written in a hurry as it had been ordered by the participants of the seminar in Göttingen: David Hilbert and/or Hermann Minkowski, and was quickly accepted for publication in order to precede the publication of H. Poincaré's works. If that was the case, then the work "Zur Elektrodynamik bewegter Körper" from 1905 would be plagiarized. Finally, the third possibility is the most radical one.He goes on to argue that Einstein’s famous 1905 relativity paper was really ghost-written by Hilbert and Minkowski, in order to steal credit from Poincare. Einstein would not have been capable of writing such a paper himself.
His theory is too radical for me, but the author does explain why the explanations given by Einstein and historians have holes.
Einstein did not reference Lorentz and Poincare, but Einstein often published the work of others without attribution. Everyone agrees to that. The only question is how much Einstein knew of other work. The Einstein historians say that Einstein knew about the older works, and that his 1905 paper independently rediscovered relativity. If Einstein knew about Lorentz's 1904 paper and Poincare's short 1905 paper, both of which were available to Einstein before he wrote his relativity paper, then Einstein had nothing original.
Poincare, Hilbert, and Minkowski were mathematicians. When they wrote about relativity, they are more precise, and they turn it into a more coherent theory. Einstein's 1905 paper is mathematically sloppy. I do not think that it could have been ghost-written by one of those mathematicians, unless he was being deliberately sloppy.