You should ask the charitable organization what the terms and conditions are for the tickets. If these are the 4, 1-day park hoppers that Disney routinely grants to charities then, no, they cannot be upgraded. Disney donated 4, 1-day hoppers to an organization I volunteer for and we featured them in a silent auction last week. In the terms and conditions for the donated tickets, Disney states "Please note, the passes are valid for two years from the date issued and cannot be upgraded nor can they be applied towards a package to meet eligibility requirements".