If you're guiding through a guide scope you don't need to match the F/Ratios. The guiding software does a really good job at keeping stars within a fraction of a pixel so your 102 F/5 should do fine.
One issue you are likely to come up against is a difference in flexure and mirror slop between the guide scope and the Edge 9.25. Both telescopes cool and flex at different rates and presumably in different directions. Your SCT is also likely to suffer from some mirror slop to some degree.
What this means is that your guide scope can do a great job and keeping its star from moving and you can get a great guiding RMS but still get star trailing. This is where an OAG comes in handy as it keeps guiding with the flexure of your Edge 9.25.
To answer your question, you can guide with your 102 F/5 but there is a chance you may run into issues with longer exposures. Only one way to find out though
