Hey James,
Would you want to share your .svg file? I can take a look. Make sure you follow those guidelines and remove and raster images or objects that are defined by clipping. When I export .svg files I use the SVG 1.1 standard. If your .svg has text in it, make sure it’s outlined or expanded (I can’t remember what Inkscape calls it). Just wanna remember to make sure that everything in your .svg is scalable with independent paths. I don’t have inkscape on this computer, just Illustrator, but it sounds like what you would want to do is the equivalent of going to Object > Expand Appearance in Illustrator.
If you have text in the image then you need to use “stroke to path”. It’s under the path tab.
I think some shapes in inkscape have to be changed using “object to path”. It’s also under the path tab at the top.