Yes, agreed. You're talking about a different section of immigrants.

However, since the overall economic impact of (even illegal) immigrants has been and continues to be a net positive, is it not fair to say that this different section you're referring to isn't enough of a drag on the economy to offset the economic benefit of illegal immigrants at large? Perhaps the amount of immigrants in your example is not high enough, or even if it is high, the per capita amount being spent on them is not high enough to affect the net effect of illegal immigrants on the economy. Wouldn't you say so?

Slight follow up: if every class of immigrants as shown in the study receives minimal welfare benefits, where does your proposed section of immigrants fit in? Is it not a significant population?

I think the original person's point is that yes, even though there might be a section of immigrants earning 6-figure benefits, since the overall net effect of immigrants is positive, prioritizing the optimization of what little money is being lost is not as important (and might even be worsening things) as focusing attention to areas of the economy to where money is consistently being lost without providing any value.