Can a radon mitigation sys make the house drop on that side?

It is common for concrete to crack at s. In fact the one thing any concrete manufacturer or installer will guarantee about concrete is that it will crack. It is the nature of the material. Concrete shrinks as it cures and really never stops curing. So the cracking at your radon mitigation hole is not uncommon unless it is starting to heave. That is it is starting to lift or separate vertically at the crack. Settlement is also normal in houses and does not necesarrily denote a problem. Avoid calling the mud-jacking company for ysis just due to the fact that mud-jacking systems are what they sell. The only way to truly determine if excessive settlement has occurred is to monitor over time. An evaluation by a structural engineer (who doesn't sell anything but his expertise) would be the route to go first, then they can recommend the best possible means of repairs if any needed.