From reading the Board Presentations, I surmise that the Capt did not deploy the TRs due to a change in habit patterns resulting from the change between Autobrakes and Manual Brakes procedures. SWA training was cited for minimal training (sounds like none to me) on using the Autobrakes. Presentations indicated that SWA crews reported a delay activating the TRs for the first few times they used Autobrakes.
There were no mechanical problems found with the plane, and if you watch the presentation, the TRs deployed with about 1200 feet left and started working w/ about 900 feet left

One of the recommendations is a requirement for the PNF to confirm depoloyment of the TRs after landing. Sure hope that doesn't happen.