Finding that matomo is massivly under reporting compared to GA. Found that if I do a export of the page URLs from mataomo there always seems to be a maximum of 1000 unique pages, but in analytics we have 20k unique page urls for that same day.
I have done some checking of the analytics API and done some quick testing and it appears the reporting API defaults to a page size of 1000 results. I made a quick modification in the following file Google\GoogleQueryObjectFactory.php after line 58 I added $request->setPageSize(100000); and did a quick import and can now see its pulling all unique url page views through.
However it only gets a couple days, maybe a months of data before it crashes.