It sounds like it's time to move from the desktop Monarch experience to utilizing the [URL="http://www.datawatch.com/_products/monarch_bi_enterprise_server_fb.php"]Monarch BI Enterprise Server[/URL] product.
This will allow your group to extend the resources that you've already built with Monarch and benefit from existing Monarch knowledge and skills, which definitely have quantifiable value, especially when comparing the cost (and risks) of possibly learning a new tool set.
You'll find contact information on that page so that you can speak with someone who'll be best able to answer your questions and address your needs.
[URL="http://www.datawatch-central.com/webinars/AQ_Monarch_BI_Server_Brochure_English_Version.pdf"]Monarch BI Server Brochure[/URL] (not the "Enterprise" version)
[URL="http://www.datawatch.com/product_literature/Datasheet_MBIES_Branded%20Format.pdf"]Monarch BI Enterprise Server Brochure[/URL]
"We have to use Monarch in the browser" is, if you don't mind my saying it, putting the cart before the horse, in that the requirements aren't yet clear enough to give you the right advice.
What do you use Monarch to do with this database? At present, I guess you have an ODBC connection from the desktop, which won't be available after the switch to a browser-based interface.
Instead of trying to replicate directly the ODBC connection to the underlying tables and queries, you could try two different approaches.
Firstly, you could use DataPump, on a server, with a web interface, and configure DataPump to connect via ODBC or OLEdb to the data source. Then you could run your projects (configured as DataPump processes) and deliver the output to the users by email, FTP, NTFS (Windows network drive file system), Sharepoint, RSS, ...
Secondly, you could generate reports from the database at the frequency you need, and ingest these reports immediately into Monarch BI Server or BI Enterprise Server (the difference is largely one of scale). These reports are then stored, indexed using your models, and you can query the datasets pretty much any way you like. There's even a Cube module in the Enterprise version to allow you to deliver interactive graphical representations of the data.
What's possible, and what's best, depends on both the technical environment (distance to the database, connection options, response speed, permissions...) as well as your requirements for output (Excel, PDF, graphs, printing/screen, usability...).
Hope this is helpful, even if just as food for thought...