This is a reported credit, not yet a fully verified one. Japanese-language listings connect George to a 1988 Nissui commercial for “Umi no Pilaf” (海のピラフ) and describe a full-body merman (半魚人, hangyojin). No viewable copy of the spot or production credit has surfaced.
Descriptions of the missing commercial mention scales, webbed hands, a dorsal fin and gills. Without the footage, those details remain search leads rather than a material or fabrication record. The reported 1988 date would place it beside A Nightmare on Elm Street 4 in his filmography. An earlier 1986 title, Collector, may or may not have been a commercial at all.
The attribution remains provisional until a copy or credit frame appears.