That’s quite a bit above the 750 safety limit!
Resampling back to the list means it’s going to need twice the memory to store the audio buffers.
I’d recommend not resampling if processing that much, and just get the chains out in a zip file.
And if you’re using Safari, that number of files is likely to cause problems as Apple limits how much of the systems memory a page can use by a greater degree than Chrome/Edge.
As an aside, I think I need to add a setting to remove the processed files from the list to help with memory pressure on large jobs.
Also, try pressing the Escape key to clear away the processing message, it might be out of memory, but still have where it got to on the resamples at the top of the list.