Do PCIE Splitter Cards Work for GPU Mining?

This motherboard has 2 1x slot and 1 16x slot GPU: 3x RTX 3060 Ti on splitter + 2x RTX 3080; on latest hiveos stable:

you can put raid cards in 4x slots, some times you have to mod the 4x slot so the back is open Alienware M17x-R4

pcie 8x slot Name: Servidu PCIe Splitter, 25CM 8 Pin to Dual PCIe 8 Pin Graphics Card PCI Express Power Adapter … Country of Origin: India

pcie slot bracket PCIe cables and not using daisy-chained or splitter cables, as these may not slot on the motherboard or pins, have you tried reseating it etc If