Or possibly further embarrassment for yourself.
Should that be
"Or possible further embarrassment for yourself?".
No.
My comment was in response to your post and would be read by normal persons as meaning :-
"Or possibly [cause] further embarrassment for yourself."
It is possibly not any less ambiguous to write :-
"Or possibly, further embarrassment for yourself."
But then "Or possible, further embarrassment for yourself" has a different meaning altogether.
Possibly, "Or possible further embarrassment for yourself" as suggested by you has the same meaning as "Or possible, further embarrassment for yourself".
Ponsonally, I have no doubts but what do you think?