Unfortunately, Mr. Heins premise for saying this is false. Heins said in an interview with CNET that Samsung can't provide "top-notch" security because Android is an open system. The trouble with this idea is that open doesn't mean insecure. More often than not, open systems are actually much more secure, because many of the people trying to hack the system are also submitting back to the platform to fix the security holes they used to get in. The biggest "flaw" in Android's security is that it most versions don't babysit users and make sure they don't install something harmful (although 4.2 does scan sideloaded apps). If you stick to the Google Play Store, or whatever option Samsung may offer as part of Knox, there really shouldn't be any issues.
But, saying that wouldn't get BlackBerry headlines, so Mr. Heins had to say something bombastic, and play on the fears that many people have because they misunderstand how open systems work.
That's not to say that Samsung Knox will be a solution to rival BlackBerry, but we certainly aren't going to be swayed by fearmongering. We'll wait to see for ourselves how Knox performs.