ShoalLogger is not showing up by default in asadmin GUI Configurations => cluster-config => Logger Settings => LogLevels => Logger Name.
Workaround is to explicitly set ShoalLogger using following cli command.
% asadmin set-log-levels ShoalLogger=CONFIG
% asadmin set-log-levels --target <clustername>-config ShoalLogger=CONFIG
I noticed if I manually added ShoalLogger to glassfish/lib/templates/logging.properties,
that this addresses the issue.