I think there must be something else going on in your case. This fork wasn't exposed to the same problem as on the main Merlin firmware. After the initial scan at boot, the networkmap code in the fork is event driven when it detects a new device or change to an exiting device or a change in network topology. It doesn't initiate any network traffic on a 1 hour timer like the Merlin firmware (and there is no ~20min timer in the fork).
Additionally, the DHCPREQUEST sequence you are seeing, is actually initiated by the printer (it's the router responding to a printer request to renew it's address).
Finally, I've been wanting to change my laser printer (a Brother 2270DW) from being USB attached to a server to a network printer. I took this opportunity to make the change, connecting it one of the router LAN ports.. That printer has been sleeping now for over 2 hours without waking up.
My best guess is there is something else on your network that is activating the printer. One thing I would check is antivirus programs, such as ESET and Avast, that do network scans trying to log on to detected web pages (assuming your Samsung has a web page for configuration/status).
Sorry, but I don't think there is anything for me to fix here.