This is a situation where all appearances are that it's on "the Chromium side" that the bug exists in that something that should be exposed to the screen reader in a standard way isn't being exposed. This is particularly indicated by the fact that Firefox, which uses an entirely different rendering engine, doesn't have the problem, and you know the webpage code has to be the same.
Now, what I don't know is the best way to approach this. I have no idea how to file a bug report/trouble ticket or similar in such a way that all Chromium-base browsers would receive the fix. I believe most of them do use the updated Chromium core code as it gets released, but I'm not 100% certain of that.
There are times when it may make sense to file a bug report with your screen reader's developers (NVDA, in this case) since there tends to be a far more consistent and open communication channel between the organizations that build and maintain screen readers and the various web browser development communities than any end user has any ability to tap. But I don't know if this is the case here. I am going to flag Quentin Christensen on this message to have him weigh in.
This is a gray area as far as whose cage should be rattled initially by the user(s) having issues.
Brian - Windows 10 Pro, 64-Bit, Version 2004, Build 19041
It’s hard waking up and realizing it’s not always black and white.
~ Kelley Boorn