Congratulations on the flowering!
I have exactly the same experience, the buds do not develop into flowers and are then aborted in the spring. But if I put the plants in the warm house, the buds develop and some of the plants come into flower. However, I have not been able to obtain fruits after pollination in that case. Apparently, it was not warm enough in my house to get healthy pollen. What did happen a couple of years ago, is that the decaying flowers caused a few plants to rot. So, you might want to keep the plants in a dry place in your house until the flowers have dried up completely.
Another thing I did a couple of years ago was to put the hernandeziis in a darker place in my greenhouse (from early August on). In that way, buds did form but stayed quite small and some of them survived until spring and then flowered. I could successfully pollinate these flowers and got fruits with very viable seeds (and many seedlings afterwards). This year I am trying that method once again for several hernandeziis, although I have put them under the shelves later than the first time. A few others were put high in the greenhouse and these have much larger buds than those placed rather dark under the shelves. I expect, however, that these high-placed hernandeziis will not come into flower and that the buds will probably shrivel in early spring.
Wolter ten Hoeve.