Wtf how hard can it be to send a text saying "I found yo earring"?
She said it in the chapter, she thought they were having fun so she didn't want to interrupt maybe.
Well to be honest though, I guess she doesn't know just how much weight that earrings had that she didn't think for a second that they would throw every plan away to find it. She probably though she would just be sad but eventually move on anyway.
...Still think she should've said something, not like a single message of finding it would hurt anyone.