I wanted to close the loop for Mellanox and the public on this issue. Unfortunately we were not able to motivate the network engineer to try the configuration changes outlined by Mellanox.
As a work around to the Intel based Supermicro transceivers, we purchased Mellanox transceivers to connect to the Arista 7050 (which to our surprise actually cost less than SMCI). After we had the onsite hands re-seat all the QSFP+ passive couplers with the new transceivers and the onboard Mellanox chip we were able to bring up all 4 nodes over LC cable.
Case closed.