> It makes no sense to bother individual translators with such a miniscule job
You're not bothering them if you're paying for the job. On your part, all you need to do is to set up a web-based interface that makes it easy and fast for them to log in and add the translations.
You're not bothering them if you're paying for the job. On your part, all you need to do is to set up a web-based interface that makes it easy and fast for them to log in and add the translations.