This one can be completed with two controllers. Plug in a second controller and then on your main character use the console at the top right of the bridge area to add a second character to your game. Follow the on screen instructions to join on your second controller and select one of the pre-generated characters.
Then start a mission. I created a Tarot mission and increased the difficulty to extreme just to speed things up a little (I'm sure it could have been set to higher quite safely).
Once in the mission use the second controller to move your second character forward and get them killed. After that clear up some of the enemies including any melee types with your main just to make things easier.
Head to the second character's body and hold
to revive them. At this point the enemies are probably firing at you, position yourself so that they have to shoot through the second character to get to you. Once they die again revive them and rinse and repeat. All in it took about 30 minutes to get the 50 revives but I'm sure this could be sped up on higher difficulty or with more enemies shooting at you.
EDIT: Check the comment below by Rengrave for some extra advice and optimisation.