The general relativity-based description of gravity you've provided is no more in conflict with a quantum (i.e. particle) theory of gravity than Newton's Laws a

The general relativity-based description of gravity you've provided is no more in conflict with a quantum (i.e. particle) theory of gravity than Newton's Laws are in conflict with the Schrodinger equation. They're just different tools that are applicable to different domains, and if we had one without the other, or if the two were inconsistent, we would definitely have an incomplete model of physical law. This isn't just some sociological quirk: The three other forces of nature are well described by quantum field theories---with plenty of experimental data to back those theories up. So why would the fourth be any different? It's just that gravity is the weakest force by far, so its QFT machinery is the hardest to observe.