The liveatc.net archive for DCA Tower 0130Z is back up. Here's what I'm able to hear. Times are based on minutes after the start of the archive.
~13:00 JIA5432 checks in with local controller on the Mount Vernon Visual for runway 1, controller gives winds, asks if they can accept 33
~13:20 "Yeah, we can do 33 for JIA5342."
~13:30 "At the Wilson Bridge, change to runway 33, runway 33 cleared to land."
JIA 5432 reads back landing clearance
~15:45 first call of traffic to PAT25 occurs: "PAT25, traffic just south of the Wilson Bridge is a CRJ at one thousand two hundred feet [partially intelligible, maybe "circling to"] runway 33.
[transmission missed]
"[partially intelligible, might be "visual"] separation approved"
~17:25: "PAT25, do you have the CRJ in sight?"
[transmission missed]
"PAT25: pass behind the CRJ"
[background commotion in tower at 17:48 probably witnessing the collision]