Wal-Mart video tapes almost everything that happens at every register in the store. I know, I spent 7 years working for them. They also have video camera's at all of the high dollar merchandise or high theft items in the store. High dollar is anything over $100 or thereabouts.
All FFL holders have to keep their records in a "special file"....it's called a logbook.
They have to keep the records for 25 years, or if they decide to stop dealing, they have to forward all of the files to the ATF immediately.
As for the trace, unless the FBI tells them about one while doing the NICS check, or the police contact them, they have no way to know about it.
I still have many friends who work for Wal-Mart as managers, and I called one of them, and he doesn't know anything about blacklisting....
Bell and Carlson makes almost all of the factory composite stocks that aren't plastic..... they are the OEM supplier for Remington (except for the M24 system and police rifles), Weatherby, Winchester, Browning......
I'm positive that the only Vanguards that have B&C stocks are the MOA series, and they aren't the Medalist stocks with bedding blocks, they are the regular Carbelite stocks that have been pillar bedded. The one at Walmart is a plastic stock that's been painted with the textured spiderweb finish. Same stock that's on the Varmint Special (not the MOA version). They are a HUGE improvement over the Butler Creek plastic stocks that used to come on them.