Don't believe the screens. It reminds me of one of my own adventures..

more or less the same thing happened to me last year, I got re-routed south to Atlanta from Minneapolis to get back up to the NE (PHL, I think) due to a 'weather system' it was on Delta and not being a regular I got pushed back, so eventually arriving in Atlanta to be met by the agent saying I had missed my onward and to go to the CS desk.
I checked the board, the flight had closed/left, but my iPhone app Flight Track Pro was buzzing, showing it was delayed at gate C?, I explained to the agent that is was showing delayed on my app, she totally ignored me, talked to the space above my head and printed a BP for the following morning, breakfast and dinner vouchers and a hotel voucher, dictating to me to follow the signs for the courtesy bus, "what about my bags, toiletries?" "your bags will be in Philly, here's an overnight kit, next"

A lady passenger behind me was stressed saying that her daughter was waiting in the arrivals at PHL and the flight was showing as delayed also, I said so was my app and it showed it was leaving from gate C??... so we both decided to make a run for it and got to the gate just as the last passengers were boarding.

I stopped and explained to the lady it was all about body language and confidence now and the boarding tkts we had for the following morning did not exist and we were getting on that flight with our original tkts.
As I presented my old BP, the gate agent looked at the screen was about to query it, I explained that we were a late arrival and we needed to get on the flight as previously arranged and were instructed by the previous gate staff to get to the gate ASAP because we were in with a chance of making it blah, blah, blah etc.. (awfully polite but determined) and he let us both on, we just sat in 2 spare unassigned seats.
When we got to PHL, there were our bags waiting... they had got there by the original route from MSP.

Moral. Don't believe the screens and don't worry about your bags, they fly around the US without you.
(After this, I personally double check and check again anything I have to do with Delta or thru ATL)