Please, please, please do not sign anything without first speaking with a personal injury attorney and  a workers compensation attorney on the matter.  Although it is s doubtful that the settlement with the at fault driver will preclude you from collecting workers compensation (they are two different claims) in some states one can be a set off against the other in a claim.  How they play against each other will best be known to an attorney in your area that deals with these matters on a daily basis.  And how the waiver and release are worded needs to be read by someone who is in your corner.  You do not want to preclude yourself from getting all you deserve. Good luck.