Let's suppose that your interpretation is correct, that Jesus said, "if he will not listen to the congregation, treat him as a pagan or tax collector."
This congregation must have taught with Christ's authority, since Christ could have said, "take it to ME," rather than, "take it to the congregation."
So this congregation taught with Christ's Authority.
Yet we know from other passages of Scripture that Christ also founded a Church. Did Christ's Church teach with His Authority? If yes, then this "congregation" would have to have been a part of Christ's Church, possessing the same body of doctrine, without which it could not settle disputes. If not, what purpose did a fallible church serve?
And why would an obscure congregation teach with Christ's Authority, unlike the Church that He founded?
This mis-translation is logically incoherent.
Suppose again that Christ was referring to any "congregation" to settle disputes among Christians. How could congregations with contradictory doctrines settle disputes?
This congregation would have to possess a non-contradictory body of doctrine, and would have to meet the above criteria, which ultimately proved to be an incoherent position.
So, since Christ’s Bride is invisible the congregation is a group of invisible individuals. Gotcha.