The context of this was that Zelensky was being asked about corruption in Ukraine, and he was hinting that maybe USAID and State Dept might also have a problem.
I don't think it would be corruption there tbh. More like bureaucracy, red tape. Like the OP says a lot of such funding is conditional or earmarked for specific things and checking all that is difficult.
https://www.yahoo.com/news/ukraine-received-less-half-us-083...