Love your posts searcher, do u have your own site? You should. Scriptual only pointers for worried dubs or summat😀
And you notice the "two or three" are "witnesses"in other words anybody is competant to be a "witness "(as you correctly point out to the sin itself)NOT elders.
Then to go to the "congregation"to put forward your grievence - in other words heard in public and it does NOT give anyone type of person MORE POWER or SWAY in the DECISION MAKING PROCESS ie judicial commitees are not scriptually sanctioned in fact these factors point to them being enphatically unChristian as held
Go first to your brother and practise christian forgiveness
Not !Behind closed doors
Wrong Giving Elders the final say not congregation
Witnesses must be to the sin not accusation
sex crimes are not included in 2/3 witness rule
Finally with no resolution, be as tax collectors - for whom Jesus still showed love