Abby82 I added that they aren't even needed because the belts are safe and they are just making life harder.
I am telling you this here because I know that it will not influence the outcome of your request, but in reality, they do fulfill their function. Without them, masturbation is possible, obviously a full masturbation that ends in something minimally similar to an orgasm is not possible, but the possibility of sliding the fingers under the outermost part of the shield exists without the bands.
Abby82 and would lenghtening the space between them make them easier.
It sounds as preparing a "Plan B" more acceptable for your father.
Abby82 I also added that of course it would even help a little if the space between them was lenghtened.
What is the length of your chain? Sorry, I do not remember.