When using Tor over VPN, the data going through the VPN's server is already encrypted for Tor, but your IP is visible to the "black box". Your anonymity should theoretically still be in effect even if someone reads your traffic.

When using VPN over Tor, the data itself isn't encrypted by Tor anymore, but the IP isn't your original IP, but the exit node's. Your anonymity depends on how you paid for the VPN (Monero > Cash by mail > Credit card).

There is no evidence that the Tor network is compromised by the US government. It's an open source network run by many volunteers all over the world. No FBI or CIA agent is ever gonna tell you to use Tor.