Sassy....
Yes, they can do that. I also have Santander for my car loan, and I did NOT reaffirm the car loan debt with them. My car loan was showing on all three, then in May while I filed, they removed it from all three agencies. After my bk was final in mid August, I called up Santander and asked them to report again, and was told since I didn't reaffirm the debt they don't have too.
If you reaffirmed your car loan with them, and your BK is final an discharged, they should start reporting again. If your bK is not final yet, and you did reaffirm, just wait until your discharge, they should report again.
In my case, I've been paying a car lain with them for 15 months now, and since I didn't reaffirm the debt, I'm not getting the credit for it and it doesn't show. I've never been late either, and was never behind. This is an account is good standing too
so, I'm desperation looking to refinance ASAP to get that paid off and showing again! Good luck!