Cruz did know and went public with it in March 2014 as written in the National Journal. He refused to do any more work for the NRSC, and he also refused to step down.
Yeah it is worth noting that McConnell used the NRSC to fund opposing primary candidates to both Paul and Cruz.
So did Cruz go public before or after the damage was done?
Sounds like after...just like the Corker vote, etc.