i will tell what i usually do. i check group stats daily, this person just got below -100. i usually wait 2 days to see if they make any giveaway on their own volition, i dont want to be too pressing. after that if nothing is done i inform them they are below the limit and ask them to fix ratio and wait some days more.
now for your giveaway you can ask them for reroll or tell them to fix their ratio and then send the key. personally i would give the key and see what he does after, it is your choice how you want to give your keys away.