In /system/priv-app/, look for "HtcLockScreen.apk" and "HtcLockScreen.odex" and change the files' extension with your favorite root file manager. After that, reboot (a hot reboot will do) and you should see your stock 4.4 lock screen.
Note: Since this isn't Sense's main lockscreen, it will be buggy. Widgets don't work, motion gestures don't work, and camera shortcut isn't there. When widgets are enabled, HTC's clock shows up (deformed) instead of the stock clock. Pin/password/pattern/face unlock all work (although it might be a little hard to set up pattern as the circles aren't visible. Or that might be default, I don't really know).
Uploading pics soon
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