Is there anything stopping you from just using cmd prompt then instead of calling straight to your application?
If you already know that using the command prompt, and then typing "C:\Program Files (x86)\.....>Application.exe...." works, you can just use that method.
Just change your file pathname to point to cmd.exe (so its the command prompt), and then put in what you normally would for the argument. And don't forget that the paths will need quotations around them if they have a space somewhere. Since this is placing a string into cmd.exe you want those quotations to be carried over as well. So you need to do syntax like \"" for a quotation. Because just doing this " somewhere in there, it will get removed. I put an example of one I do that works. I wanted quotations around the paths.