Will my ODD SATA cable port on mainboard support additional SATA111 M.2 ssd HD card while 3 other SATA drive bays are being used?

I've now solved and remedied the initial issue, which was to get, a dual M.2 B-key and M-key NVMe SSD's on one PCIe card connected to a PCIe drive port and get a SATA data connection on the Mac-Pro 2-3,1 mainboard that hadn't been flashed with any Apple-firmware updates. I resolved this issue by customizing a SATA data cable to connect to an empty SATA HD data-port on the main-board. Which then connects directly to the SATA connection on the PCIe card. The device manager recognized it immediately for initializing. Now both M.2 B-key and M.2 M-key are working and mounted together with the PCIe card as the host of the M.2 B-key and M-key SSD NVMe SSD's. Thanks again for the assistance with the directions.

Thanks, Grant, That awesome had crossed my mind for the optical drive suggestion, on the use of an ODD SATA port instead of the PCIe use of M.2 B key. Thanks also for the heads-up on windows not recognizing the ODD SATA port. As I've since asking used an alternate M.2 B+M key PCIe on a separate rig, which is only SATA11 that worked fine, so I'll switch over the PCIe cards over to the Mac Pro, to see if that also work, as that first attempted PCIe card I used in the Mac Pro was a gen3- X4 card. Which using a lower spec card may resolve the issue, with a lower spec NGFF PCIe M.2 card. Thank you so much for your feedback.