I have come across the same warning when I executed the different version of the Denodo Monitor start-up file with a different Virtual DataPort server update. However, I was still able to launch and use the Denodo Monitor as expected.
Regarding the JMX error, I would suggest you to check if the port number (required for Denodo Monitor) is available and not blocking the Denodo Monitor from launching.
Suppose, if you still need help and if you are a user with valid support access then you can raise a support case in [Denodo Support Site](https://support.denodo.com) so that our support team can help you.
Hope this helps!