Yes with numbers like those.... there's no telling what it was.
I personally am very sorry to hear this.You had a great success with him in the beginning too (as ive read).
Chin up ! ..and focus on seriously in depth study of the species/habitat (or rather more of it). See if you cant right this wrong (when YOU read/find it,YOU will know it) by a future success.
I mean who knows (i sure dont) it could in fact be a very easy solution (once found out).
You did get further than most didnt you ?
I mean they are known for difficult husbandry are they not ?
Just food for thought and all that,and again my condolences.
...it's all a matter of perspective.