man-made waterways and ambiguous platting techniques

I'm working on a project where there is some ambiguity in lot boundaries due to the method used to show the lot boundaries and the perception of the ownership of a canal-

this was platted in 1970-

The "waterway" as shown was a muskrat/beaver channel thru a wetland that was dredged in 1969 to make a passable canal- old-timers say you could navigate it in a canoe prior to dredging.

The lots are now all privately owned, with the HOA owning parcel A.

The contention is that the lots are riparian and that the sidelines of the lots go to the low watermark of the canal.

Unfortunately, the canal doesn't appear to be actually part of the lake.

The lots are as shown- the lot owners are paying taxes based on the nominal dimensions of their lots ie 75x195 while the hoa is paying taxes on parcel A which calculates out to be the meander line, which in this case is shown as a SOLID line along the east'ly end of the lots. IN some cases it's over 50 from the meanderline/property line to the edge of the canal.

I'm thinking that the HOA owns the canal and and there is no state ownership involved.

So after about 4 years of discussion. The HOA has agreed to let owners claim to the low water. at their own expense.

So I'm looking at 2 ways to do this- Amended Plat with new line work between my clients and parcel A w/ a quitclaim deed from the HOA to the clients.

or a retracement survey showing the lines extending to the low water, with new descriptions of the clients lots only, w/ quit claim deeds from the hoa to the clients.

I'm really leaning toward the amended plat route.

here is what another PLS in the area did- no deeds were filed- this land owner believes he owns to the water/"state ground".

redacted cos