Chat history when 3rd user added through @feature on accident - HELP

I accidentally added someone to a group chat using the @ and then clicking the add someone to a chat.  Normally it prompts me to choose to share the chat history, but in this case it just added them.  Did they receive access to the chat history?  It never told me they received access to the chat history when I removed them so I think I'm ok.  There is a lot of sensitive information in this chat so want to make sure I am good.  Thoughts?