well does your C# program use VISA? While possible I very much doubt it would. And looking at your C# code it should be not difficult at all to replicate it in LabVIEW. I suspect your C# program accesses the port in a different way and looking at that code would give you some clues.
Sorry for my late reply，This week I went to ask them for a C# program, and they gave me a demo. In fact, their programs do not need to use VISA. I put the core code of this demo in the following pdf, can you help me see how they do USB communication? And how can I implement it on labview？The picture below is the result of running the program, and you can see that the program has received the signal from the device.
Thanks for your help.
By going through the sample C# code ,i can suggest you two things .
Please know that device is detected as a non VCP device in your PC as you are passing PID and VID as parameters.Hence you cannot use the normal serial port functions to access that port.
And also please install the LibUSBDotNet C# USB library in your PC so that you can access the device using .net constructor and you can replicate the same program in LabVIEW or you can create a class using Visual Studio and use the same class in LabVIEW.