Do we have any actual gold in Fort Knox anymore?
There hasn't been an audit of the gold in Fort Knox, at which time the audited storage lockers had seals put on them. All those seals have since been broken. Officially, no one knows when or why. Some think much gold may have been replaced by bars of tungsten clad in a layer of gold. There is probably much reticence to do another audit for fear of what it would find, or not find.
Left out "hasn't been an audit in decades"
I'm sure the Fed already knows whether it's gold plated tungsten or not. If anything funny has gone on, the Fed was probably in on it.