I see u have access to a madcatz device now… any chance you could take a look at how the xinput driver works in sfv?
That I cant do without loads of work 
Anyway, from what we have seen with dantarion, sfvdinput is more or less obsolete because the implementation of dinput in season 2 is decent enough (with hotplug and all). If you wish to keep sf5dinput as it is you may. (Note: if you want to remove the dinput settings you have made in SFV in order to full rest on sf5dinput you have to remove the Input.ini file in Users/youruser/AppData/Local/StreetFighterV/)
I will maybe fork the project at some point to make a generic dll in order to have a generic dll for any fighting game (for a better support of hotplugs mostly).
So even with the latest patch from crapcom, my sfv would now hold down inputs by itself. So it looks like sf5dinput is still useful. Also turn off steam overlay.
I lost 1000 league points because people kept poking through my frame trap, I thought I was just pressing buttons slow, as it turns out the latest patch was dropping inputs and sometimes inputs would stay held down when I was pressing nothing.
Also fwiw, I have a feeling the dropped input has something to do with having a mouse plugged in at the same time as a controller. I noticed even my windows would be unresponsive until I start task manager. I normally just use the tracker on my laptop, but now I’ve noticed dropped inputs with a mouse plugged in.