The thing is did you fit a water block? did the card work before you fitted a water block? With water blocks the card maker can change components used at any time, as i found with a KFA 3090 the water block EK said it was compatible with it, but when fitting i could see it looked ok but when checking carefully it didn't fit properly. I had to mill out a part of the block to get good contact with GPU
also stop part of the socket used for fans shorting out because cut out wasn't deep enough. also backplate screws were to short with the correct size thermal pads which kept the back plate away from rear circuit board. its so easy to just follow instructions, but you must check every detail before turning on the PC just 1 short could mean a dead card.
Sorry to hear your card is dead, but if you did fit a water block and the card was working before you fitted it, then ultimately it must have been your fault. expensive mistake.