People forget what Windows used to be. In Win3.1, when you had a window open with icons, the nature of the icon defined a list of legal operations for the object underlying the icon, an early object-oriented list. All files had Copy, Delete, Rename (subject to permissions). Other options? That depended on the file type being something for which a known utility was available; otherwise, you wouldn't get Open option (but might still get an Open With... option.)
If you right-clicked the RUN option, Windows built a RUN dev:/path/object-name command, which it then executed by passing it to the command prompt. To even SEE the RUN option, the object had to be an executable type such as and .EXE or .COM file.
Double-clicking a file with a known association to a utility would prefix the name of the utility using the "implied launch" syntax with the name of the file selected file. That would go to the CMD utility as "system-path/utility-name user-path/file-name"
If you clicked DELETE, Windows built a DEL dev:/path/object-name command, which it then executed by passing it to the command prompt.
Drag-n-drop between folders generated a RENAME command, etc. etc.
Windows 3.1 almost ALWAYS passed the command it had just generated to DOS and the CMD utility.
When Windows NT came along, that paradigm changed only in that DOS was no longer underlying the operation - but CMD is still there hiding in the wings.
The question is whether if you copy that string you showed us (using CTRL/C for COPY) and then open a command window and paste it (using CTRL/V), will the "Command()" function correctly show the "test" parameter? That ISN'T using a shortcut, that is using the "real thing" in terms of process creation.
Note that the ONLY reason I am suggesting it is because it is an easy test to perform and I know exactly where that command option dumps the excess of the command line after the launch of the utility. I think that test WILL show you the "test" parameter - but if it doesn't, we have found a point of difference regarding the environment. If it does as I expect, we haven't actually found anything unexpected.