Adding managed DHCP to an existing smart proxy failed

Problem: I was trying to add DHCP (and TFTP for PXE provisioning) to an existing smart proxy and it failed with this error in proxy.log:

Error details for Disabling all modules in the group ['dhcp_isc', 'dhcp'] due to a failure in one of them: File at '/etc/dhcp/dhcpd.conf' defined in 'config' parameter doesn't exist or is unreadable: <Proxy::Error::ConfigurationError>: File at '/etc/dhcp/dhcpd.conf' defined in 'config' parameter doesn't exist or is unreadable

Expected outcome: for the DHCP feature to be installed and configured successfully

Foreman and Proxy versions: 3.13

Foreman and Proxy plugin versions: katello 4.15

Distribution and version: Oracle Linux 9.5

Other relevant data:
Command used was foreman-installer --foreman-proxy-dhcp true --foreman-proxy-dhcp-gateway “192.168.0.1” --foreman-proxy-dhcp-managed true --foreman-proxy-dhcp-nameservers “10.202.17.6,10.201.18.6” --foreman-proxy-dhcp-range “192.168.0.10 192.168.0.99” --foreman-proxy-tftp true --foreman-proxy-tftp-managed true --foreman-proxy-dhcp-interface eno1

I saw posts about the issue from 5 years ago related to CVE-2020-14335, so first I checked and yes, the /etc/dhcp dir was owned by root:root rather than root:foreman-proxy, so I changed it and tried again. No luck. Saw another post suggesting a service restart after making the ownership change, which did resolve the issue. Is this a known side effect of the mitigation that just never made it to docs or did I find a bug?