Roundworms cause some $170-ish Billion a year in damages. There have also been Chinese caught smuggling certain fungi into the US.

No doubt. Importation of pest animals, insects, plants, and the like is a serious matter. Citrus canker decimated Florida's production a while back.

But that doesn't make this "bioterror," or convert the roundworms into a "bioweapon."

I'm sure there is a perfectly innocent explanation why the University Of Michigan keeps having the incidents where their researchers keep smuggling potentially harmful things into the United States.

Probably not "innocent," in the sense that they were flouting and/or willfully violating the rules against importing certain plants and animals. Clearly there's something wrong with their institutional controls there. But like with any illegal smuggling of animals or plants, it's probably not a "bioterror" situation. If China wanted to illicitly introduce roundworm as a pest insect to damage U.S. agriculture, there's far better (and easier) ways to do it than having very small numbers imported using ordinary import channels by scientific researchers. Just have actual criminal smugglers sneak them over the border and release them. The far more plausible explanation is the simplest one - these people wanted to do biological research and didn't feel like following the law, and thought they could just get away with doing what they wanted.