HRA;
This is very interesting...please give the Bosch PN on side of the Dist, and I will see if I have Dist data and put further info together for you...bottom line is that this is, I expect a fairly rare failure (actually first time I've ever heard of it) but if you can file a new keeper notch into the spring mount, and be confident it will stay and not pop off in service, I expect it will be a good long-term fix, and replacing the Dist is not necessary.
It's great that you identified and repaired the root-cause of the issue...clearly the second advance Spring (for upper RPMs) was completely out of the picture, so your advance was too high too early, and that completely explains the "pinking" (on this side of the Atlantic: Pinging!).
Ref:
https://www.sw-em.com/Volvo%20Igniti...CA%20Servicing
I'd also be interested in any pix you might have of the damage and repair.
Cheers