The river has been changing channels now for a couple of centuries. Eventually it comes out at Morgan City ~ and that's a certainty.
Did you see what the OHIO FORK (the largest Mississippi tributary) did at the end of the last Major Glaciation? It cut clean through the limestone floor to connect with its upper reaches ~ you need to read about the TEAYS river to get a feel for it.
The Ohio is actually larger than the Mississippi (in CF/M) where the two join.
Fortunately for the lower reaches of the river, the flood control features built over the last 80 years along the upper reaches seem to be working decently so the flood should be over sometime this year rather than next year!