What does this prove?

At one point 3M produced Adrenochrome.
This patent was allowed to expire so production must have moved on to another method. There are a LOT of these Adrenochrome patents.

What are the odds that 3M would have the "white rabbit" in it's past?

Process inventor Deryck Boot.
In 2011 he was still working for 3M.
Australian patent for Metered dose dispensers

But he only ever worked on two patents.
Adrenochrome in 1981.
Drug dispenser equipment from 2003 to 2011.
https://patents.google.com/patent/AU2011203017A1/en?inventor=Deryck+Boot

Deryck F. Boot works for Senzer Pharmaceuticals since April 2016
"Senzer offers an opportunity to supply next-generation products to ...populations who ...have a high need for specific molecules..." https://senzer.com/ 

I'll state for the record that a couple people are telling me Sir George is a good guy, and that very well might be true.

But the coincidences say 3M probably did what it needed to, to make $ in its early days. Certainly not a smoking gun, just suspicious.