Hello, did you applied for a translator on their platform? Why there's such a blackmail approach that they wouldn't offer more if you didn't do it? Usually project translation comes with a first come basis right? Participants should apply to each and any upcoming bounty project if ever. If that's the case then they giving you privilege to be chosen for translation every time there's an open campaign for translation?
I was a translator on their platform for years and I applied for this project SCI without knowing it was 17k words of WP to translate. It got confirmed after weeks and by that time I had a surgery done and told them I can't do it after which the reply was:
Or you can of course not do it at all, which means you will not be rewarded for it and won’t be able to get other translations on the platform.
It is first come basis only but you once you apply and are chosen after a month or so, you cannot withdraw your application.