I'm not super well versed in legal issues, but can conflict of interest be a true concern in two privately-held companies? (I'm not challenging your sentiment as much as I am genuinely asking out of curiosity/lack of knowledge.)
It's different from organization to organization. In this case, it would be easy to say the preferential treatment granted to a former employee (even though they had higher bids from other companies) could be deemed a conflict of interest.
From the NFL's own Compliance Plan:
Generally speaking, a conflict of interest arises when an employee has a competing interest or loyalties that are, or could be, at odds with each other. These competing interests may occur as the result of engaging in outside or other personal activities, or due to personal relationships.
The personal relationships between the former NFL employee and the current employee in that same position could easily be seen as a conflict of interest.
Yeah, no conflict of interest there huh?