Avi, I think the RCA and Agudas get along a little better than the Gra and early Chasidim. It’s not really opposition like that.
For years, just about all American gerim have been funneled into RCA beis dins. So, if the RCA did anything stupid (like went off the Avi Weiss deep end) it would create a lot of mamzers. I imagine Agudas “keeping them in check” helps keep this from happening.
Do you have any examples of when the RCA has ever “kept Agudas in check?”