Keeping the vehicle in orbit is essential to studying the issues, which occurred on the Starliner spacecraft’s service module — a cylindrical attachment that sits at the bottom of the spacecraft. The service module will be jettisoned and discarded as the capsule returns home from space.
Because the service module won’t be returning with the mission, engineers will not have an opportunity to gather more data about the technical problems after the astronauts land
So not an issue that would affect a return, they just want more time to look at the thing that had problems before they have to throw it away.