This is moving too fast.
Gao Yi wanted to throw out bait by offering US$300,000 to see if Grasse was interested in making money and whether he could pull him into the scheme.
The benefits of doing so were numerous: first, to gauge Grasse's attitude, then his capability, and besides, the US$300,000 was a total sum, but Grasse would be paid based on the amount of work he did, and it might not be necessary to pay in full in the end.
But Grasse even wanted to gulp it all down in one bite, honestly, it wasn't that Gao Yi was unwilling, but that he didn't quite trust him.
From this moment on, the tables had turned.
Desirelessness rendered one immune to all poisons, but once one coveted the US$300,000, Grasse had to demonstrate his skills to the person paying—the "father" of the contract.