Im sorry, we Protestants (including us ex-Catholics) are already members of Jesus Church. Maybe not so fresh after a lifetime, but still members.
Meanwhile, I know plenty of Evangelical churches that are just chock-a-block full of former Catholics who got saved and left the Catholic church as a result.
If Protestant spouses wish to receive the Eucharist, wy don’t they revive their dying cells and convert to Catholicism as have many other Protestants including leading Lutheran theologians?