Your cards will fit fine with EK-Quantum Vector Water Blocks with standard backplates included in the kit.
The Active Backplate is an add on kit that replaces the standard backplate with an active backplate, for my card RTX 3090 FE it was a pre-order option when I purchased the QV block.
So yes if your running the active plates, you will need to get out the dremel. lol
I never thought to check the top slot for clearance till after I ordered the board, truly wish EVGA could have went with the x4 slot above the top x16, foresight would have prevented clearance issue.
The open-end x4 slot at the bottom may have issues with longer cards shorting out on the CMOS battery.