مَا أَنَا قُلْتُ هَذَا وَلَا غَيْرِي
Neither I nor anyone else said this.
When the initial fronting is meant to contrast the speaker with another possible agent, adding «nor anyone else» defeats the purpose of that contrast. The first form points away from the speaker toward an alternative attribution; the continuation denies all alternatives.
This is a point about the specific rhetorical interpretation under discussion, not a blanket claim that the sequence could never be meaningful under any imaginable context.