Autochair themselves, who make most of the hoists used, have a large record of successful uses, I’d suggest you phone them, and another fitter. Bear in mind that there are a lot of variables that no fitter can have complete experience of, and they are liable if they just say “yes”.
Recent cars: Hyundai Kona Ultimate EV; Volkswagen Caddy Maxi wheelchair accessible; Skoda Enyaq iV SportLine; Vauxhall Mokka-E; Kia Soul EV, Hyundai Kona (again)