LibreOffice ExportToEpub Filter Doesn't Honor FilterData Parameters

I use the following LibreOffice Basic macro code to export a Writer document to an EPUB file:

exportArgs(0).Name = "URL"
exportArgs(0).Value = exportURL
exportArgs(1).Name = "FilterName"
exportArgs(1).Value = "EPUB"
exportArgs(2).Name = "FilterData"
exportArgs(2).Value = Array( _
	Array("RVNGCoverImage",0,imageURL,, _
	Array("RVNGTitle",0,docTitle,, _
	Array("RVNGInitialCreator",0,initialCreator,, _
	Array("RVNGDate",0,Format(Now(), "yyyy-mm-ddThh:mm:ss"),
dispatcher = createUnoService("")
dispatcher.executeDispatch(exportDoc.CurrentController.Frame, ".uno:ExportToEPUB", "", 0, exportArgs())

While the above code succesfuly produces a valid EPUB file, the parameters provided for FilterData – exportArgs(2) – are essentially ignored. When I import the resulting EPUB file into Calibre, the Cover Image, Author (InitialCreator,) and Date are simply not set as specified by the code.

This page indicates that the parameter names I’m using for FilterData are legit.

If I use .uno:ExportTo rather than .uno:ExportToEPUB in the dispatcher command, a dialog is displayed pre-populated with default values: Cover Image URL is blank, Author is populated with the First and Last name as set in LibreOffice’s User Data Option, and Date is populated with zeros. If I manually enter data for Cover Image, Author, and Date; the Image and Author are recognized when I import the resulting file into Calibre. But Calibre displays the date/time of import regardless of the above code’s reference to Now() for the RVNGDate FilterData parameter.

I have tried using .uno:ExportDirectToEPUB in place of .uno:ExportToEPUB without seeing any change in behavior. My question is:

How do I write code that will export a Writer document to an EPUB document in such a way that I can specify the Cover Image, Author, and Create Date/Time within the macro code rather than requiring me to enter the data manually?

Any suggestions would be appreciated.