location ~ "^(.*)/wp-content/uploads/(.*)$" {
  if ( !-e $request_filename ) {
    rewrite "^(.*)/wp-content/uploads/(.*)$" "https://***.com/wp-content/uploads/$2" redirect;
  }
}

location ~ "^(.*)/wp-content/cache/thumb/(.*)$" {
  if ( !-e $request_filename ) {
    rewrite "^(.*)/wp-content/cache/thumb/(.*)$" "https://***.com/wp-content/cache/thumb/$2" redirect;
  }
}