The word "lost" is a little bit confusing in this context. It successfully landed and operated several days, but it's location was only approximated.
We've seen landers in recent years that crashed unintentionally in precise known locations. Does this mean that they were not lost?
Lost can be not knowing where something is or to no longer have it.
Yes. Generally, if you know where it is, it is not lost. If you don't then it is.
But, it also depends if you want to know where it is. If you don't know where something is and don't want to, its not lost its discarded.
Yes, the word "lost" is ambiguous, but I didn't even notice the ambiguity until you pointed it out. I think the presence of the word "found" in the same sentence lead me to assume the "unknown location" sense rather than the "destroyed" sense.