Claymore is the CEO of Monero?
Is it true?
No. He is not.
He only developes the miner as far as I know.
But one should stick with open source miners. This way you are not dependent on a single piece of software you can not control to get your rig running.
If you only got a few CPUs or cards, it not a big deal, but if you own a farm, you can get in trouble very fast with AMD and a closed source miner.
Speaking of network safety: Just imagine a closed source mining software for AMD GPUs that stops working on a specific date in the future. It would cripple the network down to less than 50% nominal rate and leave it exposed to all kind of nasty things... you do not want that. Really.