Holly is Innocent
The clues are all there:-
She is human.
She is too cool when kidnapped by Nada.
Her neighbours are spying on her.
When Nada tries to interfere with the telly she has to get rid of him fast.
She does not necessarily call the police. The police are on his tail and can track him plus the neighbours were suspicious.
She was with the resistance.
She surprised them all by misleading statement as if she had told the truth beforehand.
She is genuinely sorry for attempting to kill him. She almost knew there was about to be an attack on the resistance an that they had already been rumbled and were being eavesdropped.
She had to go into work as normal. She is deep undercover.
She wasn't in the office but skulking about somewhere else.
We did not see her kill Frank. There was a cut beforehand.
She may well have tried to stop him attacking the transmitter.
Nada had turned around and had dropped him gun. She could of killed him there and then but she just asked him to come down with her.
She knew that the swat helicopter was on its way and that Nadas actions would lead to his death.