The RFA tender has little to do with the Bills thinking that Whitner >>>>>>> Wilson. This is about protecting an asset. There WILL be a market for Whitner and with this tender, plus his status as a former first round draft pick, the Bills could receive a nice bit of compensation in the form of a high draft pick or two in return. Plus it sets a market price for Whitner's services which will likely be more realistic than it sounds like he thinks it is and that could be used as a basis to sign him long term at a reasonable price or wave bye-bye to him if another team wants to overpay.
Wilson was undrafted, therefore the only way the Bills could receive compensation would be if they tendered him at a very high amount and paid him a 2011 salary that is way above his talent level.