Arknights Welfare RS-EX-2 Clear, Challenge Mode

The Rides to Lake Silberneherze level RS-EX-2, Signal Light, Challenge Mode, cleared using only Welfare operators.
Again, the trick here was to get a bunch of Emergency Heaters up, running, and stabilized quickly. After that, I set up two kill zones, with blockers plus arts and physical damage ranged operators. The hope was to defeat enemies before blocking was too much of an issue. As a result, I didn't use any healers. It works.
Welfare operators are as defined at:
arknights.wiki.gg/
wiki/Operator/Welfare.
Comments and advice are always appreciated.