Arknights Welfare TG-3 Clear, Challenge Mode

To the Grinning Valley level TG-3, Unsafe Exit, Challenge Mode, cleared using only 5 Welfare operators.
Gladiia was able to handle all the enemies who came across the top. For the approach across the bottom, Puzzle, Harold, and Astgenne took care of things. I added Czerny just in case, but it looks like he never actually saw any action, so I could have cleared this level with only 4 operators.
Welfare operators are as defined at:
arknights.wiki...
wiki/Operator/Welfare.
Comments and advice are always appreciated.