Try to use this command:"
python splitdata.py .../big.json
to split file in more mini.json. In this case you will can ingest json's and find which file is broken.
for example :
after splitting will have:
big-1.json
big-2.json
big-3.json - broken
big-4.json
big-5.json
continue to insert 1,2,4,5 - and than try to split again big-3.json ... infinit than, you will find broken file, which you can repair manually.