Plugin cannot be installed:
Installing Plugin: ManageWP Worker 3.9.29 Downloading install package from https://downloads.wordpress.org/plugin/worker.zip… Unpacking the package… Could not create directory.
Apache is member of pscln group.
Make sure that Apache is not member of pscln group on Apache Service Node:
[root@apache_service_node]# grep -ir psacln /etc/group psacln:x:506: