NASA update a few weeks back said all 27 thrusters passed multiple hot fire simulations of the return mission. That overall things looked fine. And they still felt safety factor of riding home on Dragon was better.
Kinda neat that there are multiple options now. NASA mission leaders felt the same a while back. Even if Starliner seems fine to come home why take even that slight bit of risk.
This is not what I’ve read.
Boeing engineers tested the thrusters and managed to replicate the issue. They found that there issue was caused by a bulging of a Teflon valve.
However they don’t understand the root cause of why the Teflon is bulging.
So Boeing said it’s safe for the astronauts to return on Starliner but they also said that they fixed the thruster issues they had on the previous flight.
Not all NASA is confident that the Starliner is safe enough.
IIRC, the whole thing is a bit of misconception in the popular imagination. It’ll reenter just fine if it manages the right maneuvers. The risk is hitting the ISS on the way out.
And actually making those maneuvers. If the seals bulge again and disable a thruster, they might be unable to control their flight.
Was this update. About five minutes of update starting at this timestamp.