On the other hand, the legislative powers have recognized that SLAPP lawsuits are a problem - there are certain issues that need to be decided equitably in court even though the power (read money) differential between plaintiff and defendant is just to great. Patent trolling is probably a subset of SLAPP.

Following that reasoning it's fair, I think, that a minor in immigration proceedings should be appointed a lawyer by the government.

Sure. GOV has no obligation to represent either side in a bit between private parties. The curve for me is that the children in question are on the other side of the "v." from United States.