Ah ok, that looks like a bug on our end. We'll add it to the tracker to fix for next plugin update.
If you need a workaround for now and are amenable to editing the plugin file a little, I believe commenting out the Draw Text call on ln 793 should do the trick. This will still allow you to use Deck Points as a mechanic while not displaying it under the Card Preview.
Let us know if the issue still persists after this change and we can troubleshoot further if necessary :)