OER also has official ranking lists going back to then. Where the dates are at the top of the page, you can use that to go back in time (the womens goes back to the start of 2015). On the last normal list prior to lockdown on 16/3/20, 110 points would have ranked 407-409 and 117 points, 389-391.
Just comparing her to the other u18 wunderkinds, there's only Katrina Scott and Maria Timofeeva who've got any significant points from 2019: Scott 46 out of 145 points, and Timofeeva, at least 20 out of 129 points. Timofeeva has a few other two point or one pointers from 2019, but I don't know if they're counters in her overall ranking.
I know someone suggested there may be an issue with the LTA but I really think Matilda might be missing out on the mutual support and encouragement she'd get if she played in some of the UK tournaments. Those players who played in the early tournaments at the beginning of the year seem to have pushed on really well.