In that case you'll need to set things up similarly to what @Amethyst1 did in this thread, essentially requiring two separate Thunderbolt docks and two Apple miniDisplayPort to dual-link DVI adapters. If you have two Thunderbolt 3 docks, then you'll only need one Apple Thunderbolt2-to-Thunderbolt3 adapter and a Thunderbolt 1 or 2 cable to connect the laptop to the first dock, and then directly daisy chain the second dock into the downstream port of the first dock. You would only need a second adapter if one of the docks used the older Thunderbolt 1 or 2 standard.
The above is only accurate if you have a Thunderbolt 1 or 2 dock, not Thunderbolt 3, sorry for any confusion.
If the adapter is from Apple and has a lightning bolt on it, then it's definitely a Thunderbolt2-to-Thunderbolt3 adapter. I don't believe Apple ever made a USB-C to mini-DisplayPort adapter (only third parties). The Thunderbolt2-to-Thunderbolt3 will be needed to connect the dock to your Mac, and a USB-C to mini-DisplayPort adapter would be needed to connect a
Apple miniDisplayPort to dual-link DVI adapter to a USB-C/Thunderbolt 3 port.