I finally got my work laptop connected to a Thunderbolt dock that charges it, drives my peripherals, and drives my 4K monitor. It was not as easy as it should have been to set up, though. It does not help that my laptop has a USB-C + charging port, and a Thunderbolt 3 report (that also charges, though that wasn’t clear at first). I was not sure why I could not charge my laptop through the dock, until I noticed the distinction between USB-C and Thunderbolt, and I was not sure why my Thunderbolt-to-DisplayPort cable would not work from a USB-C port in the dock. Having the same ports/connectors does not make USB and Thunderbolt easier to deal with: it makes it harder.