Ah sorry, no you can't. The inspector shows all available selectors and the ID isn't one of them.
becc5f70-f620-4558-a4a6-95b8fab42a1d-image.png
(The matrix columns can be addressed through the ID but I thought I've added it here to, but apparently that's not the case).
But yeah if you're almost there, just go with your own dragger. Note that there's a snippet in the example database that also gets you 80% there:
https://docs.hise.audio/tutorials/ui/index.html#drag-modulated-parameter
