It’s because he’s a pacifist, he wouldn’t want to work with Cecil because he wouldn’t want to use his powers for military/violent purposes, which Cecil would want him to do.

As to why he would choose to work with the Maulers instead I would imagine his plan was to betray and abandon them somewhere they couldn’t do any harm

He has to surely, in order to break the maulers out. Plus surely at least one of the alternate-dimension Angstrom’s would have known about it

But out of left field and a bit dated but Zenith is vaguely similar - even right down to the blue and yellow