I'd love to correct you, Nero, but you are correct. The team finances are from the most recent sim, not considering pending actions. Now, once you got the over the cap warning it should have showed you over the cap. I need to probably consider including pending contracts and cuts in the finance display at least for your own team.
The game in its original state did not allow you to make offers that sent you over the cap. During beta testing this caused issues in free agency because you couldn't sign players without first making cap room, so it was decided to allow you to overspend and have the game stages cut players for you if you were still over the cap. What I didn't consider is how that would affect renegotiations during the season.
I've put this on as a high priority fix to not allow you to sign anyone that takes you over the cap during the season, hopefully before MFN-2 hits their season. I did put the players that didn't get snagged back on your roster and opened back up some cap room, but it's a little bit too far gone to try to undo the one that got signed by NJY.