@eericmatus1,
Although the "Sci" in "SciFi" stands for science. But, don't forget about the "Fi" part (which is an important part of "SciFi"). If you are writing Fiction, you should be happy writing fiction.
1. I am wondering how your claim that "no one will find a graviton" impacts your story. It works fine as fiction.
2. Your explanation that the "these forces cause space time to warp" is not scientifically accurate. Neither is your description of "centrifugal force".
3. Your question about a "moving mass" is not specific enough to give a scientific answer. You need to define a frame of reference, and once you do that the question might be mathematically trivial.
In Relativity there is no absolute motion. Whether an object is moving or not moving depends on the frame of reference (or in other words, the observer). Are you taking this into account?