Ambiguity vs Basic Understanding.
If your company is organizing a function and your boss asks you to make arrangement for the food catering, would it be ambiguous to you or your boss that you or the company is expected to pay for the food? From an outsider's perspective, if he sees a person agreeing to make arrangement for the food catering without knowing the whole context of the conversation, it may be ambiguous or he could even conclude that you who agree to make arrangement have to pay for the food.
But the boss should know very well that although he arrows you to make arrangement for the food, the company aka him, will pay for it.
The same applies to NEA-Hawker-WP AHTC saga.
If we do not know the context or the relationship and obligations, such statement made may sound ambiguous or may even make us conclude that the hawkers will pay for the arrangement of scaffolding. But the truth is, AHTC itself has already declared that it knows and understand the rules and obligations for it to pay for everything, including the scaffolding, for the cleaning of hawker centres, including the scaffolding.