Plugable USB 3.0 dock -- exFAT formatting support for Win7 64-bit?

This Plugable USB 3.0 dock (ASmedia chipset) does not appear to support formatting SSDs in exFAT format under Win7 64-bit (which another brand of dock with an unknown chipset which was used previously can do successfully).

Example: with Windows 7 Ultimate 64-bit, dock connected directly to Silverstone SST-EC04-P PCIe expansion card (no hub in between); when attempting to reformat Samsung SSD SDSSDX-480G-G25 the exFAT option does not appear at all in the drop-down list of formatting choices (only NTFS).

These SSDs are used in digital video recorders, and are completely reformatted before each use.

We worked with Nigel via our email ticketing system to discuss this issue, and are posting the results below in case they will be useful to others:

We were able to choose exFAT on our test systems, and were unable to determine why this issue was occurring on on the customer’s system.

I did however find a workaround for drives that aren’t presenting the option to format with exFAT - we can force it via command line. From an elevated command prompt:
format x: /FS:exFAT /q

-Please make sure to use your specific drive letter rather than “x”!
-The “/q” switch is only needed if you want to do a quick format of the drive. If you’d like to do a full format, omit the /q switch.
-If your drive has a label, you’ll be prompted to enter it for confirmation before the format will proceed.