GoFundMe campaigns can only be managed by one person, the account creator. We're unable to give other people the ability to log in and manage your campaign. By default, the Campaign Organizer is also responsible for handling the withdrawals.
If the donations you're raising are for someone else, you can add them as a Beneficiary and give them a separate account they can log in to and make withdrawals from. Read one of the following articles for more information on how to do that: