"In connection with the Greenshoe Exercise, the Company received gross proceeds of $450 million and net proceeds... of approximately $446.6 million ... to use for general corporate purposes, including making investments in a manner consistent with the Company's Investment Policy."
This new investor will almost certainly ask that their post investment ownership is equal to investment/(pre-money valuation + new investment), or in other words that existing convertibles are included in the pre-money valuation.