I was bitten by this too. Why doesn't your team include the renewal price for domains in the 30-day autorenew notices? This whole class of problem would disappear if you did.
To be clear, I work on Google Registry, not Google Domains. I don't particularly know anything about Google Domains other than basic generic information that applies to all domain name registrars. I can't even say that I know what most parts of the Google Domains UI even look like, let alone the 'why' behind them.
The renewal fee is on the domain management panel.
Not the question. Why is the information behind several clicks in a settings panel and not in the renewal notice?
Because they are embarrassed about the renewal price, of course. ;-)