Their sabotage attempts of several bridges in Crimea did not go this well, suggesting that the Ukrainians alone aren't the best at understanding explosives, and their successes like "fly a bunch of FPV drones out of a shipping container" are quite a bit simpler than this. "Intelligence agency" is a spectrum of capability. Suggesting that an intelligence agency that tried and failed to blow up a bride twice was the same as the one that executed a flawless operation against an underwater pipeline is a bit far-fetched.