The sheriff didn’t say he was radicalized, he asked whether he was radicalized “unbeknownst to us”.
So he doesn’t have evidence he was radicalized, he wasn’t asserting he was, but it seems he was open to the possibility and investigating for it
http://www.breitbart.com/big-government/2017/10/04/sheriff-vegas-shooter-get-radicalized/
I get it. The shooter was radicalized into embroidery. Or maybe became Amish. Yeah... the last scenario makes the most sense!