Will electron produce gamma rays?

Question is, do electron exist anyway?

One quick note: While gamma rays are typically more energetic than X-rays, the true difference between them is what their source is.

If a highly energetic photon comes from an electron's interaction with something, it is called an X-ray no matter how energetic it is.

If a photon is emitted from nuclear reactions inside an atomic nucleus, it is called a gamma ray.

As such, even if the photon created in your scenario were of the energy levels typical of gamma rays, it would still be called an X-ray.

As for your question, I've forgotten enough of that corner of physics that I would need to spend a few hours refreshing myself before trying to answer. Hopefully someone else will know the answer.

But what if an electron as a particle doesn't really exist?