Can a runway have a displaced threshold and a closed section in the same area?
In any case, threshold and runway numbers are highly desirable in a new position. Possibly it is the reason why pilots were confused with your initial variant.

At least by FAA regulations, if you don't want to allow takeoff from this area, it should not be a displaced threshold. I believe that you have a relocated threshold (part of runway closed for takeoff and landing). It can still be available for taxi though, but you don't have a taxiway from that end of a runway. It should look like this:


FAA reference is here, in "Partially closed runway" paragraph.

I saw partially closed runway in Europe as well, and it looked like that (actually they marked that part as a blast pad, and I saw that several times):



Unfortunately did not find anything similar for Canada (used Canadian AIM), but "relocated threshold" is mentioned in some accident investigation in Canada: report. And I still don't understand why the runway should not be marked just as "closed", without threshold displacement markings. Like here:



Arrows may confuse pilots, because it usually means that that part of a runway can be used for takeoff, or landing in opposite direction.