I'm sorry but it is a little difficult to compare the flower on your neighbour's plant with your flower. Is a photo with a larger flower possible in an orientation that is face-on so that the two flowers are easily compared.
Looking at this photo of your neighbour's Stella suggests to me that they are not the same cultivar, but that opinion may be affected by the flower size and orientation of your neighbour's Stella in the photo. Did you both buy your Stella plants from the same nursery and in the same year?
In any case, aborting pods mainly within a week of pollination is a characteristic of incompatible pollinations. That is very difficult to understand if both plants are true 'Stella de Oro'.
