@cmonlai
you can just pass the values to the parent element using the data object on the close function of the first lightbox like so:
wixWindow.lightbox.close({data: yourDataHere})
https://www.wix.com/velo/reference/wix-window/lightbox-obj/close
Then on the parent page just pass the data into the second lightbox with
wixWindow.openLightbox("name", {data: yourDataHere})
Trying to open one lightbox directly from another open lightbox is not possible and will give you the errors that you are seeing. The parent page HAS TO BE the intermediary to handle opening and closing of multiple lightboxes and passing data between them. There is no other way to accomplish this task