If the Revcloud is one whose vertices all fall on the original rectangle shape, and that is orthogonally oriented [as in my previous Reply], this seems to restore the original, without the chamfered corners in the PEDIT/PLD results, whether or not any vertices don't fall on the original corners:
(defun C:REV2REC ; = REVcloud to RECtangle
(/ revc verts)
(if (setq revc (car (entsel "\nSelect orthogonal-rectangular Revcloud: ")))
(progn ; then
(setq verts (mapcar 'cdr (vl-remove-if-not '(lambda (x) (= (car x) 10)) (entget revc))))
(command "_.rectang"
"_non" (list (apply 'min (mapcar 'car verts)) (apply 'min (mapcar 'cadr verts)))
"_non" (list (apply 'max (mapcar 'car verts)) (apply 'max (mapcar 'cadr verts)))
); command
); progn
); if
(princ)
); defun

That's in simplest terms -- no verification of appropriate selection, etc. -- but the usual enhancements can be added. And I assume you would want to delete the source Revcloud [I didn't have it do that yet, so you can compare it with the resulting rectangle].
Kent Cooper, AIA