Your use of non-HPE disks is a cause because they're not reporting proper temperatures to the RAID controller.
The ILO controls thermal settings on this platform and the hysteresis curves that govern fan speeds.
I commissioned the work of a developer who wrote a machine-language hack that exposes ILO fan controls to the SSH command line. This ...
If the links to download firmware are dead, your only hope is to get your hands on a ProLiant Support Pack that does support your server hardware.
I don't have my HPe login near, but check there for older version of it;
HP Service Pack for ProLiant
As stated in comments, please advise your customer.
Your link for the HPE Offline Bundle for ESXi 6.5 tells you what it contains. It's drivers and similiar utilities from HPE, it's not any VMWare ESXi software at all.
The VMware site link is for an ESXi image bundled with those drivers, which would easily explain why it's a lot bigger.
You have a failed drive and a failing drive. Replace both.
Storage media wears out relatively quickly, even when handled properly. And if these drives are the same vintage as the server they are aging.
For "is this circuit safe" ask an electrician. Seriously, electrical fires are no joke, and some old wiring is terrifying.
Regarding a rough estimate on draw, that's not how redundant power supplies work. Properly sized, each could carry the load of the system if the other failed. For what that load is, make an estimate with component ...