Hi,
Thank you for the details, I think I know where the problem might be. Unfortunately the log-in does not allow me to access the search options to confirm.
I looked at the items via the developer console, and after loading 40 more items, they disappeared, but not removed. I think, that the pagination still triggers, even though it is invisible. To completely get rid off the pagination, change this option to a high number, like 500 or so: https://i.imgur.com/pYrtGjd.png
If the rows count is very high, then the pagination should not trigger whatsoever. You can also remove the custom code, that you use to hide the pagination, as once the row count is increased, it is not neccessary anymore.
I hope this helps!