Are you using OMSA version 7.4? On the systems that are failing, are they VMs? as we've seen similar issue when accidentally installing to VMs.
Try this. For OMSA install issues, you can install OMSA using the .MSI file instead of the setup.exe. When you use the .MSI for installing OMSA, you can use some parameters to specify the install log location.
1) Download and extract OMSA
2) Go to a command prompt and navigate to C:\OpenManage\windows\SystemsManagement
3) msiexec.exe /i SysMgmt.msi /l*v "C:\openmanage\logs\SysMgmt.log"
This will place the install logs in the C:\OpenManage\logs folder.
Let me know if you can send me the logs. I will send you my email.
Have a great weekend.