When you delete a file all that does is mark the space as free.
Until that space is over written the data is still there.
I suppose you could get a wipe free space tool and let it run.
As for how long google keeps records on their servers ask google.
I found the CNET article, "Stop Google from tracking your activities" and went to Activity Controls and paused Google from tracking me. But I have read about people who return from travel abroad, and how the TSA can make forensic searches of phones and computers, and obtain data that users have "deleted" from their devices. And if we delete Google's history, then has it been deleted from Google's servers? So how can we completely delete data from our devices?