Um, I would be careful about ingesting cadmium, my friend. Anyway, you can easily test your hypothesis on mice if you actually want to pursue this idea.
The replacement of soluble collagen with insoluble collagen with age doesn't seem to occur.
Bones are indeed less mineralized, but in a way that makes more mechanical sense i.e. less concrete, but more rebar.
Some wound healing pathways are inhibited, but it's scar tissue formation that is inhibited. Repair and remodelling as seen in dolphins takes place instead.
Kidneys indeed excrete things they don't normally do, but it seems to be an active process, where larger molecules are moved through, not leaking.
Also stable levels of cadmium are sought, its levels are regulated, excess levels are excreted.