First of all, no they didn't. They only delayed it 15 years. (That is if they obey the agreement).
Secondly, yes it may be a technical issue, or it may not be.
BTW, it blew up, yes, but you don't know that it self destructed, or if the Iranians destroyed it intentionally. Maybe they learned what they wanted to learn by then, and/or were concerned that it might be going astray at the end.