Here's a shitty translation:
Do you not animate the rest? I am not involved in the production, so it's really... I'm sorry that it's because it's the original work that it's hard to sell even if I make a polite animation carefully.
I believe he's saying that due to the nature of the remaining chapters of GLT, it would be difficult to make a continuation of the anime. Probably both because there aren't enough chapters left for a full anime season, and because of the subject matter.