>>/9719/
I didn't see ponibooru.org image #4000 in these:
. "old" JSON: https://web.archive.org/web/20220727065923if_/https://ipfs.infura.io/ipfs/QmZLFVYNBa7c7AmfvBttbuM19hmh1LftcLDrmQDeW6gXqT?filename=list.json
. "new" "JSON": ipfs://QmfAUaWbRrqMesYa95AkkfcUtFD5nVQLyWdpTGVJfbDD14
. didn't search for this file: "medium-age" JSON

(Reminds me: pin the folders that ponibooru.org links to in both computers.) I (re)generated the directory listing JSON:
> rclone lsjson --drive-list-chunk 0 --disable ListR -R "remote:archive/Pony/Art/Image archives/ponibooru.org" > Pony-Art-Image_archives-ponibooru.org.json
which took about 3 minutes. Both of these found remote paths:
> $ grep "/3999 - " Pony-Art-Image_archives-ponibooru.org.json
> $ grep "/4000 - " Pony-Art-Image_archives-ponibooru.org.json
so, I gotta find the "medium-age" JSON file or regenerate it.