Possible missing standoff

Attempting to watercool a rtx 3080 zotac amp holo using an EKWB quantum vector trinity rtx 3080/90 block (first time watercooling a GPU)

Instructions say to screw in to the 10 provided standoffs on the waterblock, but my waterblock only has 9, the missing one is the top right corner screw next to the core. Do I need this to get replaced? I doubt I can just leave this screw out. Any advice would be appreciated, would rather not have to wait two weeks for an RMA with an exposed 3080 pcb lying around.

On a side note, will I need to replace the thermal pads (not sure if they'll "dry out" or anything like that).

Cheers.

Edit: is there anything I could use as a replacement, like a motherboard standoff? Edit2: I'm taking it apart again in January to install a backplate, would it be ok to only have the 9 standoffs screwed in till then? I assume temps will be higher but idk if it would be safe to run.