Botting in competitive

So im b3 in eu and i was playing few hours ago and i had a teammate in first 2 round he was botting so we couldn't dodge, after 2 rounds he started to say excuse how he didn't notice then he started to argue how bad we are and we are blaming him that he was afk, by watching his game play he didn't feel like hes bronze or silver, he was a smurf who was throwing, after that we were like 4-11 and we started to win when we get to 11-12 he went afk, I think he was a friend of enemy who was giving them free win i can show y'all replay if you want can i get my rr back any chance? btw sorry my English is bad