It seems to me that there are two pumpkin bugs, or two different set of symptoms - but the question is whether they have the same underlying cause or not.
The first bug is that some pumpkins cannot be interacted with at all. The cause for that problem is known, and is easy to reproduce. The pumpkin contained a charm and a temporary mask - someone took the charm, but left the mask. From that point, only that person can interact with the pumpkin - others cannot, until/unless the person who took the charm takes the mask.
The second bug (?) is when you interact with the pumpkin and get a text saying you found a charm - the pumpkin disappears, but you do not get a pumpkin into your inventory. Now, maybe the bug is just that the text should be "You found nothing", which is fine, or if all pumpkins are supposed to contain a charm, then something else is wrong. The strange thing is that the next time one of those pumpkins spawns, it seems more likely to fail again iin the same way - I tested that on one pumpkin - got 5 failures in a row .. it is like it gets stuck in an "empty" state.
Upcoming fixes look good...so, not giving up yet...