I have lost many a rose plant when I saw them totally ‘dead’. I have uprooted them and thrown them away. One day a plant that was not uprooted came to life and I saw fresh red shoots. That plant is now yielding.
Playing Possum is pretending to be dead as a Possoum does that when threatened. There is no reason why a rose plant should do that but they do have that dead look. After that accidental discovery I leave those plants alone and they come to life when they decide to.
There are trees in our garden that shed leaves and the tree is totally bared of leaves but they too come back to life with fresh leaves.
Have you discarded rose plants that looked dead?