Hey.. I've recently been the lucky recipient of 2 panda quests.
however, you can actually lose "Tropical Cage" buff/item, if you are still in the "nursing the cub" part of the quest.
if you have not completed "nursing the cub", and you use cage on mayor house, "tropical cage" buff/item will vanish and be gone, forever (at least logging out, and visiting other players island have been in vain.
when you proceed to next part of panda quest "return to mama panda", will not be completed, and you will need a new cage, even though you had a cage and used said cage on mayor house not long ago.
you can't use cage if you don't have quest, however, you can use the cage, even though you have not proceeded to that part of the quest yet.
meaning 2 things:
1: the cage you had, will vanish in thin air and be gone forever.
2: when being asked to own a cage and use on mayor house, it will be unsolved, even though you technically have done this, however moments earlier.
3: because of "1", you will need a new cage when proceeding to "returning to mama panda".
4: there seems to be no refund for the vanishing cage (at least I have not noticed this, and at best, the refund is 50% of cages cost.
simple solution: unable to use cage prior to "returning to mama panda"
thanks for your time. take care