I'd start by pointing out that PDF files aren't really what AutoCAD is expecting to use for a help file. HTML files are best. If you use HTML files then you can set command specific help tags by using HTML anchors in your HTML help and then referencing them in your <Command> element... e,g,
While it doesn't hurt anything, there's no need to specify LoadOnAutoCADStartup="False", as this snippet explains from a well written Autoloader White Paper:
LoadOnCommandInvocation– Load only when one of your custom commands is invoked. When using this Load Reason, you must include a ‘Commands’ element. Also, if LoadOnCommandInvocation is enabled, then LoadReasons LoadOnAutoCADStartup and LoadOnAppearance are assumed to be disabled unless explicitly enabled. Only applies to ARX and .NET modules.