At the start of the fight, his "It was me, Barry!" line was in response to a newspaper article that read "FLASH KILLS QUICKSILVER?!", referencing that particular Death Battle. It wasn't that Quicksilver died again... it was that Reverse-Flash was responsible for Quicksilver's death to begin with. He's the one who put the samurai statue where Quicksilver would end up getting impaled on its sword at the end of his fight against the Flash.
As a fan of DB idk why the fanbase gets so salty at everything, This was their first loss since Majin Buu and they do well on this channel actually (counting DBX)
I hope you feel better and get back to normal and stay safe that Covic ain't nothing to play with but you can for sure get rid of it. Stay safe now my friend and this was a epic battle. Even tho Black should of won.