Can an amend reopen an old wound?
The problem with this question lies in the question.
[This is a good example of 'begging the question', ...
... which presupposed the answer in the question.]
It presumes that a harm unamended is an old wound.
An old wound is a wound that has healed.
Of course, a wound that has healed should not be reopened.
But an amend cannot reopen a closed wound.
An amend is a disinfectant rinse.
Swill a disinfectant rinse on a healed wound and no harm is done.
Swill a disinfectant rinse on an unhealed wound and the wound can start to heal.
... even if the disinfectant rinse stings. Stinging is not injuring.
If the wound is still open, even years later, it remains a fresh wound.
So, no, old wounds categorically cannot be reopened.