I am saying that the Bryant Lab product is described (by Bryant's supplier) with the same molecular formula and molecular weight of photographic Glycin. In my tests, it behaved exactly like photographic Glycin when compounded into Agfa 8 film developer and used to develop film. In my opinion, it is photographic Glycin.
I used Agfa 8 as a test vehicle because it is a simple, single reducing reagent film developer - nothing else in the recipe is a reducing agent.
The reason for perfoming practical confirmatory testing with film, is that there is an enormous amount of conflicting information in various publications and on the internet about Glycin.
A Google search on Glycin will inevitably turn up a lot of hits on Glycin and Glycine - there are several compounds with these names and similar names, but with different molecular formulas. The principal one that shows up has medical/biochemical applications and is useless as a photographic developing reagent.