how to run multiple Gazebo simulations in Fedora & ROS 2, multimaster-fkie package not available

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I've seen suggestions such as just setting:

export GAZEBO_MASTER_URI=http://localhost:11346;

But this happens:

[Err] [Master.cc:95] EXCEPTION: Unable to start server[bind: Address already in use]. There is probably another Gazebo process running.

and to make sure the port does show a different from the default:

echo $ROS_MASTER_URI
http://localhost:11319

When I try to follow the instruction for installing FKIE multimaster for ROS on Ubuntu I get

export ROS_DISTRO=foxy

rosdep install -i --as-root pip:false --reinstall --from-paths multimaster
ERROR: the following packages/stacks could not have their rosdep keys resolved
to system dependencies:
fkie_multimaster: Cannot locate rosdep definition for [catkin]
fkie_node_manager_daemon: Cannot locate rosdep definition for [rostest]
fkie_master_discovery: Cannot locate rosdep definition for [rosgraph]
fkie_multimaster_msgs: No definition of [std_msgs] for OS [fedora]
fkie_master_sync: Cannot locate rosdep definition for [rosgraph]
fkie_node_manager: No definition of [rqt_gui] for OS [fedora]

So I believe those instructions are for ROS 1. Are there instructions for ROS 2 Foxy, or is there another way to run concurrent instances of Gazebo?