No he hasn't. (He's whined that Terrell was too negative towards Landrieu.)
See Washington Post. He said yesterday he supports President's goal of getting a Republican elected. They do expect a more "formal" endorsement at a later date. If you enter "terrell" in search function you can bring it up.
He needs to come out in support of her. As do Cooksey etal. And she needs to contact GOA and complete their survey so she doesn't have a "NR" (not rated) by her name on gunowners.org