If you have a CC subscription, you can download previous versions of Photoshop with your subscription. I have run Photoshop CS6 Extended (which is what you get when you download "Photoshop CS6"), along with Photoshop CC (2015) for quite some time. I usually just run one at a time, not both together, although I have had both open now and then.
Just click on "Previous Versions" in the CC app, to see what versions you can download...there are several.
With Photoshop CS6 Extended, the Oil Paint Filter has always run for me, even when the Photoshop CC (2015) Oil Paint Filter did not work, even though it does work now in both versions.
With Photoshop CS6 Extended, you can invoke the CS6 Bridge program from the File menu. Photoshop CC (2015) has it's own Bridge program, that is more up to day, probably...FYI.
CS6 has some features that the CC version does not have, that is why I have both. The latest, sometimes, is not the greatest...IMO. LOL I did have to manually install the latest ACR for CS6, which is available from Adobe. (Version 9.1.1 is the newest it will take)
Link for Adobe Camera Raw 9.1.1 for CS6
https://helpx.adobe.com/x-productkb/multi/camera-raw-plug-in-installer.html
The Oil Paint Program is different in both Photoshop versions, I believe. It might be my imagination, but the CS6 version of Oil Paint Filter runs smoother on my machine...and I do not think it has all the features of the CC version. (I have not researched this...might be wrong.) I do know the CS6 version Oil Paint Filter comes up faster on my machine.
The downside to CS6, for me, is that my CC app keeps telling me there is an up date for CS6, but will not update it. I spent LOTS of time trying to figure this out, to no avail. Also, I get a popup that wants me to register it with Adobe...which for me is impossible. LOL CS6 works fine in all other regards, however. I use CC 2015 the most. The ACR update is probably why the CC app wants to update CS6...however, it does not recognize that it has the newest ACR installed....LOL
I hope this is not too confusing, and hope that perhaps this info might be of some help to someone.