Chances are vanishingly small that the R760 will support ESXi 6.7.
Broadcom's compatibility guide for an R760 shows ESXi support starting 7.0 Update 3i.
The guide no longer allows you to select an ESXi version earlier than 7.0 Update 3, however.
https://compatibilityguide.broadcom.com/detail?program=server&productId=55720&persona=live&column=partnerName&order=asc&keyword=R760&activePage=1&activeDelta=50&redirectFrom=PowerEdge%20R760
Likewise, the earliest version of ESXi listed in Dell's drivers section of support for the R760 is 7.0
https://www.dell.com/support/product-details/en-us/product/poweredge-r760/drivers
Since the issue probably revolves around the model of the RAID controller, the only other option I can think of is installing an older generation Dell RAID controller in hopes that it will be seen by ESXi 6.7.