I have spotted a towing eye door - or at least that's what I guess it is - on the front bumper below the O/S headlamp.That's odd? It's a legal (type approval) requirement to have at least a front one (on any car, hybrid, EV, or otherwise). I suspect there will be an irritating pop-out piece in the front bumper or grille area (probably in line with one of the chassis longitudinals), behind which, there will be a captive nut. There should be a loose (and probably left-hand threaded) eye bolt somewhere in the back, with the jack. I suspect that's dealer BS, to be honest. My EV isn't supposed to be towed either, but still needs a towing eye - it's just for dragging them out of the way if they get stuck, rather than for towing them any distance.
I can't comment on the truth about towing, I'm just going on what Toyota told me but I suspect you may be right because all of these cars are hybrids.
There is a moulding for the towing eye in the boot, no jack though but I think there may be space for a space saver wheel......the traction battery is under the rear seat so it may be tight.
John