You can try bypass this. If you put base-t tranciever into SFP+ slot then x690 will change autonegotiation to ON and spped to 1000. Then you can try to add port to sharing.
I did something similar yesterday. Before inserting tranciever:
2:46 VR-Default E R OFF 10000 FULL NONE
2:46 VR-Default E R ON 1000 AUTO 1:47 1000T
Contact Us:Sam PirokCommunity@extremenetworks.com