I asked the developers to provide me with the Recaptcha v3 statistics for the past week. The percentage of requests that caused Scoutbook to display the I’m Not a Robot check box (Recaptcha v2) is extremely low. The resolution of the graphs is such that I can’t accurate estimate the percentage beyond saying it appears to be under 5% of the requests and is most likely even lower.
Sometimes when you get the I’m Not a Robot box (Recaptcha v2) you are asked to click on a grid of photos. This is all under the control of Google.