Steven ZahmI was able to get the file to import.
The import is done in batches of 100. Quite a while pack after testing on various web hosts I settled on this being a decent value for both shared hosts and more expensive hosts which give more server resources.
I was able to get the whole file to import by changing the value from 100 to 10 (this is a code change, not a setting). I also tried higher values than 10, but, those too, failed. This tells me it is a web host resource limit causing the imports to fail.
I see you have the PHP execution time limit and memory quite high. The thing is, you can actually set these values to anything you want, the host will “hard limit” these so you can not exceed whatever they set. My experience is most hosts do not disclose what exactly those hard limits are. I suspect that your web host has rather low hard limits which prevented even 20 at a time from importing without failing. Perhaps if you look into the PHP error log that might give some clue.
Anyway, I hope this helps!
ps. I left the code changed so it’ll only import 10 at a time.