As someone kindly pointed out earlier, BR would come into the locker room as a default leader and honestly, whether or not the accusations are true, his image is tainted and I wouldn't want him to become the new poster boy of the franchise. Additionally, if you will continue to go back into the thread, a poster points out that a former Steeler questioned his relationship with the team and that players with young daughters weren't particularly amused with his off the field actions.
Again, I am not saying any of this is true because I cannot rightly know, but I seriously do not think he is 'a perfect fit' or a 'sure thing'. If anything, I think his acquisition would have blown up in Nix's face eventually.
Addressing that bolded part - I'm sure that's what the Steelers said after the first time.