Their writer’s take on the findings is way overstated. They are not seeking or expecting to find a 5th force of nature.

The research is a more precise measurement of a muon’s magnetic moment. There is a possibility, because there are a couple ways to calculate a muon’s predicted magnetic moment using the standard model of particle physics. The researchers have said that there is not even an anomaly at this point between their experimental calculation and the standard model. There is a discrepancy between research groups coming at the problem from different ways. That does not in any way implicate any new force or deviation from the standard model… except to a bad science writer.

I'll delete the post in a minute, after I've had my coffee.