Summer holiday tactics

While the club may have closed for the summer, some members are still chessing despite the heatwave! The diagram (Black to play) shows a recent position from a junior training session with yours truly as White and one of HJCC's brightest talents Oliver Thorne as Black, which I thought followers of the website might enjoy...

First it was the turn of the (relatively) old fox to strike after Black's 1...Rb8 - what could be more natural than moving the attacked rook and threaten both the queen and Rb1 mate? Unfortunately there is a spectacular flaw, how does White win from here?

Instead we went back and tried 1...Re8 after which White should have played 2.Rxc7 with a winning position - unfortunately I tried 2.Qxc7 instead. How did Oliver punish this oversight with another tactical finish?

Both answers below in the comments box. Enjoy the summer!