Just to isolate variables, is this occurring when the system has nothing installed on it except a fresh Win10 1709 installation from regular Microsoft media (i.e. not a customized image) plus the drivers necessary for the system and TB16 dock?  The reason I ask is that I remember a known issue between the TB16 and older versions of Citrix Receiver, and that involved Citrix Receiver interfering with the ASMedia USB driver.  That issue didn't result in blue screens, but I thought of it when you mentioned that same driver here.  Just as one data point, I'm able to use my 7480 with a TB16 without any issues at all, so if you haven't already, I would start by seeing whether things work properly in a minimal Windows installation.  If they do, start installing any additional drivers/applications one at a time and see when the BSOD behavior returns.

Thanks for the reply. I only have the one device, and it's my only work machine. Due to the general flakiness I have been debating paving it and starting over, but that's time intensive and impacts productivity. Unfortunate if that's my next step. I've used Dell hardware at home and work for years and this is the first time I've had such issues, so really disappointing. 

I definitely know what you mean about the time.  Just to avoid potentially end up having to rebuild your system from scratch for nothing in case the behavior persists even after a clean install if you go that route, you could capture an image of your current state before you wipe your system.  That way if it persists, you can restore your image and be no worse off than you were before except for the time to do part of a clean install -- but at least you wouldn't have to reinstall everything else manually.  Macrium Reflect Free is a popular tool for capturing images, and as the name suggests, it's free.

I found one possible source: the Thunderbolt service and software stops running, usually when the laptop is asleep. I find if I wake it up unplugged and check task manager, the ThunderboltService service (tbtsvc.exe) is almost always stopped, and there's no icon in the notification tray. I start the service, and launch C:\Program Files (x86)\Intel\Thunderbolt Software\Thunderbolt.exe, then I can connect the dock ok. 

That is working often. Although literally as I was going to post this response the system blue screened on asmtxhci.sys.

I had this issue with my 7480 and TB16 dock. It turned out to be the latest version of the ASMedia USB Host Controller Driver (1.16.51.1)

I uninstalled from Add/Remove Programs and installed this version. System has been rock solid ever since.

Funny...I did the same thing a few weeks ago. :) Was waiting to see how the system responded before posting back. That older version is definitely more stable. I haven't had a blue screen since, and can consistently connect/disconnect the Thunderbolt dock without any issues.

Im seeing the same issue with the 7490 with the tb16

Same problem with a new and fresh Windows 10 install of a 7490. Instant and immediate BSOD when I plug in the TB16 dock.

Dell Command Update did not find the proper ASMedia USB Host driver apparently.

I updated the ASMedia USB Host Driver manually with Version 1.16.49.1, A06 and it works fine now.

As I said, Dell Command Update did not find this newer version of the driver. Strangely, I have not had this crash with any other 7480 in the office when they use their TB16 docks. Only this one 7490 and it's TB16 dock caused the immediate crash.

If you're having this issue I recommend manually downloading and installing that 1.16.49.1 A06 driver.

The AS Media USB drivers are still as unstable as can be and many USB devices will cause the BSOD. Version 1.16.51.1 still seems to be the last of the stable versions.

I had similar problems that seem resolved by asmedia driver 1.16.55.1 and dock firmware 1.0.2
https://www.dell.com/community/Latitude/New-7490-TB16-Skype-for-Business-BSOD-in-asmtxhci-sys/td-p/5843761/page/8