the problem is not a 'bungee webbing' or retainer. We know that this is there for a reason.
The problem is a bladder. You know well that the bladder end on almost all brands is sealed well before it ends and that sealed excess is used in securing the bladder in place. Sealed excess can't be pumped, so it can't be put on pressure resulting in tear or thinning (stretching), the bladder like this retainer does!!!
I can take a micrometer and show that bladder is thinner where the retainer is, due to tear. Or do this, put a watch on your hand and tighten it, how does it feel after a few hours?
Than repeat the next day...Over some time your skin would be thinner, damaged by a watch strap.
If Ozone seals the bladder at the ends for about 10-20cm (as you say) and that excess is used around the 'bungee webbing', than it would be heaps better. There is absolutely no point in having a bladder put on pressure after the retainer. The retainer keeps the bladder in place when NOT pumped. Not the opposite.
And because of that, sand and salt inside the bladder can make a pin hole on exactly that place on a pic's, as OP reported.
Not a brainer, really.
Yeah, my 1000 post