@ridwan66  Separate the WD19DC's dual connector unit into separate pieces and only connect one of them to the system. But the WD19DC really isn't a good dock choice for an XPS 13 9370.  The WD19DC is designed for the Precision 7000 Series systems because its dual connector design allows it to provide up to 210W to the attached system, enough to support the Precision 7000 Series models.  But the XPS 13 models are only designed for 45W, so the DC is a waste.  And the WD19DC when used in single connector mode behaves just like the much less expensive WD19 -- but it does NOT behave like the WD19TB, which uses Thunderbolt 3 rather than USB-C.  The WD19TB can therefore run higher-end display setups than the regular WD19 (or WD19DC in single connector mode) while still using a single connector.

So if you only need the capabilities of a regular USB-C dock, then you should've saved money and gotten the WD19.  If you needed the capabilities of a Thunderbolt dock, you should've gotten the WD19TB.

Also note that the display setups listed as supported in the WD19DC's documentation only apply when used in dual connector mode from a system that supports using it in dual connector mode, which as of this writing is only the Precision 7000 Series systems.  The WD19 and WD19DC when paired with an XPS 13 9370 can run dual displays up to 1920x1200 each or a single display up to 2560x1440.  The WD19TB when paired with that system can tap into 4x more video bandwidth, which means it can run dual displays up to 4K 60 Hz each or triple displays up to 2560x1440 each.

@ridwan66  Ok, you'll need a Thunderbolt dock to run triple 1080p from your system.  Within Dell's lineup, that means the WD19TB(S).  The "S" version dropped the 3.5 mm headset jack that was part of the previous WD19TB.  The global semiconductor shortage somehow prevented production of those jacks or the audio chipset, which was blocking Dell from producing docks, so they created variants of their WD19 dock family models that didn't have that jack.  Also note that when running triple external displays, you will not be able to use the XPS 13's built-in display.  This is because the Intel GPU in that system only supports three total simultaneous displays, regardless of resolution or how they're connected.  The first Intel GPU to support four displays is the Xe, but that didn't arrive on the XPS 13 until the 9310, which is the current model as of this writing and is four generations newer than your 9370.  Good luck!

@ridwan66  Happy to help.   Docking stations and displays can indeed get quite complicated.  Certain USB-C and TB3 features are optional, plus there are different revisions of DisplayPort that have different capabilities, so you have to look at exactly what each system supports, what the dock you're pairing it with supports, and the requirements of the displays you plan to run.  But glad to hear you've got a workable solution for your purposes!