That being said the standard model is very good at predicting outcomes at a small scale. The issue with gravity is things where General relativity applies need to be huge to be observe. If we want to find a quantum model of gravity we need to observe what gravity does at a small scale and try to fit a model within these observations. That’s why this experiment is a step in the right direction. Maybe gravity does “weird” things at a smaller scale… Back to your question we don’t know we just observe :)