An extra couple clicks does not really seem like a major stretch, especially for anything that should be secure. Worst case do what many things I have seen do,

An extra couple clicks does not really seem like a major stretch, especially for anything that should be secure. Worst case do what many things I have seen do, the act of clicking the button opens a web page that simply states "thank you for doing X". That way regardless of what platform they click it form, it works. I am assuming you are already building the functionality into a portal that managers can go to and see a list of everyone, so why replicate that functionality in email? Wanting to have this functionality in email feels like a severe case off over engineering for things we have been doing for a very long time. There are very few benefits to users but all the benefits for google. This keeps people in Google for longer. That is not something we should accept. Giving google more control.