Notes: Catdam is not needed. You can replace him with another long range heavy attacker
Try to get all your cats to be as high levelled as possible. This will make the level (and the beginning stalling part) easier.
At first, don't spawn anything. After Pastry Cat is halfway across the battlefield, start spawning your Crazed Walls. While you are doing this, level your Worker Cat to level 6. After a while, Crazed Walls will not be enough to stall the Unicycle Cats and Pastry Cat, so also start spawning Eraser Cats after a couple of Unicycle Cats have piled up.
You should try to synchronize the Unicycle Cats with your Cat Cannon since they will start quickly plowing through your meatshields, attacking one after another, which is dangerous. After you get your Worker Cat to MAX Level, spawn Crazed Bahamut Cat, then start spawning ALL your meatshields.
Now, try your best to stall the Unicycle Cats and Pastry Cat, while also stacking your Bahamuts. Continue spawning meatshields and stalling until the Unicycle Cats are dead. Once they are dead, start to spawn everything.
Now starts the nightmarish part. Try your best to spawn everything and meatshield of your best abilities. If you even stop meatshielding for a short while, the onslaught of different Awakened Cats pounding on yours will instantly kill off everything, so stay focused. If your Bahamuts die, try to continue being focused on killing the Beefcakes. If you are meatshielding well enough, the Battle should go on as normal, albeit at a slower pace.
Once the Beefcakes are dead, all that remains is Dancer Cat and Heavy Assault C.A.T., which should be way easier to beat.