The share options will be worth at least $100bn too, if the conditions are met. But meeting the conditions will require buying huge numbers of GPUs from AMD. GPUs worth $100bn, and somewhere to put them. OpenAI can't afford that - not even close.
So they need to raise financing. On the face of it, the options seem to mean that lending OpenAI the money to buy the GPUs is perfectly safe. You take the stock options as collateral. You lend the money, OpenAI buy the GPUs, the AMD stock goes up, the option conditions are met, and even if OpenAI didn't pay you back the options will let you recover your investment.
However, this loan is far less safe than it first appears. The problem is that although lending the money allows openAI to buy GPUs, this doesn't necessarily cause AMD stock to rise. Infact if OpenAI don't find a profitable use for them then both their stock price, and AMD's will go down. And you'll be left with worthless collateral and a big loan to a company which can't afford to pay it back. So they haven't actually magically created financing at all. They just created the illusion of it. It's very clever. But it's fake. The real announcement will be when or if someone lends OpenAI cash.