CalTrain equipment question

I was at the CalTreain yard in San Francisco last week and saw some outy of place equipment that I was wondering if anyone knew the story behind.

Fist was a few single level stainless steel units and second was I think four gallery cars painted white with a stripe and MTDX (Metra?).

I also saw a Sounder trainset there.

Also if anyone knows why there was a CalTrain car at the Metra yard off Canal Street in Chicago last week I’m curious about that as well.

Mark