Are all 1936 model ss/police degen's supposed to have a protective cap(or as some call it virgin cap)under the pommel covering the blade tang where there's a set screw?
Is there cause for concern if it does not appear present?
Thanks for the help.

nope

Yeah--but if it does not have it you better look it over quite carefully to see if it has been apart and tampered with in some way.

1936 SS Degens (Krebs and unmarked) must have a cap,when it is virgin. PMD Degen not.
Police degens must not have a one.

Thanks for the replies.
So how is this cap held in place and how rare or common is it to see it there?

Most of these swords will have it. It is pressed on and looks like the top of a nickel plated rivet. If you take it off and remove the spanner the sword will still not come apart-it is pinned through the tang. Further tampering is necessary to get it apart and if this is done -most of the time it is not put back together in a proper manner--so--if you remove the spanner and the sword comes apart--you know it has been rather extensively tampered with. If it does not come apart--probably someone removed the rivet head and maybe the spanner and when it would not come apart-put it back together -probably could not get the rivet head to stay on--trashed it.
It also should be mentioned that the rivet head can rather easily be replaced giving the appearance of a virgin sword. This is not an easy hobby--but I don't think any of them are.
Also--if tampered with but not altered or fake insignia added--you still have an expensive sword-not worth as much as a virgin but still worth quite a lot.