Many people say you cannot change the organizer of the event. This is untrue. You can, but it is not easy.
For a single event:
Download from Original as iCAL, open in text editor, find\replace the organizer section, upload to new organizer, cancel from old organizer without message, send updates from new organizer; alternatively, cancel from old organizer with message about the change await response, send from new organizer, await response.
For multiple, you'll have to do the same with all of them, or download all to a single ical file with a shell box (an equipment mailbox you create to pack them all together). If an entire calendar needs to be moved, just output it all as an ical from that box. Then use a text editor to find\replace all the "Organizer" entries with "Me" as the organizer (or the new email address), and upload to the new organizer. Now you can update them all as necessary. I suggest you waste a day and send up to two months of updates for that new organizer. Then do this again once every month until the calendars are all caught up. You may have to move the times and locations, but this isn't difficult. And at least you can move them.
If you want to have multiple organizers use google, or you can try this:
set up a shell ID (equipment mailbox) for each group of organizers, and give all group members send-as permission, as well as full access permission, and set a delegate or delegates who will receive responses (the whole group?). This will allow them all to make changes to the event and send the updates to themselves. (if they send as a member of a group, they send as the ID of the Group or the Shell ID; so they still get the message in their own box and can add it to their agenda, but no need to really). This logic can make or break you. Set the auto-attendant and other settings right, and it'll make your job security.
For a single event:
Download from Original as iCAL, open in text editor, find\replace the organizer section, upload to new organizer, cancel from old organizer without message, send updates from new organizer; alternatively, cancel from old organizer with message about the change await response, send from new organizer, await response.
For multiple, you'll have to do the same with all of them, or download all to a single ical file with a shell box (an equipment mailbox you create to pack them all together). If an entire calendar needs to be moved, just output it all as an ical from that box. Then use a text editor to find\replace all the "Organizer" entries with "Me" as the organizer (or the new email address), and upload to the new organizer. Now you can update them all as necessary. I suggest you waste a day and send up to two months of updates for that new organizer. Then do this again once every month until the calendars are all caught up. You may have to move the times and locations, but this isn't difficult. And at least you can move them.
If you want to have multiple organizers use google, or you can try this:
set up a shell ID (equipment mailbox) for each group of organizers, and give all group members send-as permission, as well as full access permission, and set a delegate or delegates who will receive responses (the whole group?). This will allow them all to make changes to the event and send the updates to themselves. (if they send as a member of a group, they send as the ID of the Group or the Shell ID; so they still get the message in their own box and can add it to their agenda, but no need to really). This logic can make or break you. Set the auto-attendant and other settings right, and it'll make your job security.