In my case, I can click the toggle in Customize menu to get the stats to reappear. The toggle itself doesn’t work, but I can hide/unhide the NTP stats this way. This was the only thing that I found to work.
Hope this helps and applies in your situation! Take care.
This option from @Chocoholic works for me as well. Toggle in NTP --> Customize --> Brave Stats does not work when toggling off but will toggle them back on (if desired) if they’re turned off via the three dots icon as @Chocoholic shows above.