Is it legal for the DA and Attorney to come up with a plea deal if the Attorney has not met with his/her Client about the case

Absolutely not, any sort of negotiation or offer should always be communicated to the client.  Additionally, a plea is invalid if the client does not accept it.  Now, dont confuse having a "plea deal" with simple negotiation.  The prosecutor will almost always try to negotiate to try to expedite cases.  Attorneys discussing a plea agreement does not mean having one until the client approves it.  Good luck.