Nero did not accuse anyone of conspiracy when he was in Greece.
The conspiracy again Nero (the Pisonian conspiracy) was foiled in 65 BC, before Nero went to Greece.. Faenius Rufus, one of the two prefects of the Praetorian Guard (imperial guard) was involved.. He was the only one who could be considered as someone akin a general.
Two provincial governors ( Gaius Julius Vindex, the governor of Gallia Lugdunensis, and , Servius Sulpicius Galba, the governor of Hispania Tarraconensis) rebelled against Nero. Governors also commanded armies. Their military rebellion led to Nero to commit suicide. That was in 68 BC.