In my opinion if you want some Bounderz and a regular Mangler, you should use the Squig Rider Stampede battalion and I dont really see the meaning of just 3 Rockgut.
Here my list around Squig, even with Skragrott, I chose to make the Mangler boss the general because of Fight Another Day and Skragrott is still really worth the point (+1 to cast, 2 casts...)