(1) Able to see printer when in same subnet, after selected printer, all options and the Print button is greyed out.
(2) When manually adding printer in Settings, got error "Unable to communicate with this printer."
Make sure default SNMP Community is enabled, if you have that removed, see below.
Community Name 1: (ticked)
Community Name: public
Access Permission: (ticked) Read Access (not ticked) Write Access
If Samsung is to rely on SNMP, it should either say in the application or on the printer settings page, or to offer an option to use alternative SNMP settings.
It's been a year before I figured this out. I'm slow, I know.