I personally do not have experience with using any of the mentioned tools to monitor a Fuse/AMQ instance but have had experience with many customers who have used JBoss ON or a tool such as JConsole to do so.

JBoss ON does not require admin access. A user can have view only roles to resources they care about on their dashboard without any issue or exposing administrator console like functionality. The JBoss ON UI works well for that. This also allows you to utilize the same system and UI regardless of the user's role to handle other tasks such as administration, system operations, alerting, user management, etc. Of course, this would require you to have at least one administrator that could configure users and role mappings and define resource grouping definitions that will allow a read-only user to gain access to AMQ/Fuse availability and metrics.

Many users have also used JBoss ON to capture and report on metrics and then utilized the JBoss ON client API to retrieve various data points for integration into their own charting/graphing implementation. Unfortunately, I do not have any ready made solution outside of various example scripts to pull metric data or availability data from JBoss ON. Most of this is covered in Writing JBoss ON Command-Line Scripts. Obviously, this solution would be similar to 3) except that discovery, inventory management, and configuration could be handled without the need for implementing a JMX client.

Some of the options in 2) could work. The Visualisation plug-in and Statistics plug-in seem promising but I am not sure if these are supported with Fuse/AMQ. However, many of these are going to expose administration functions and are not limited to view only and will therefore fit into the same category as JBoss ON.

If you are only concerned with service availability pulling, JMX via Nagios might work for you too. However, such a solution would still require some kind of dashboard/graphing/charting system. However, perhaps the Nagios console would be sufficient for this.