One issue with this extra scene is that if it is placed right before the Han/Kylo meetup, Leia should be telling them to evacuate the system immediately, since it’s too late for any backup to arrive in time. With that in mind, the official could head her off at the pass:
“This is Chancellor Lanever Villecham…”
“General, are you seeing this?”
“…I’m sorry General, but the Senate has decided to retain the fleet in case evacuations are deemed necessary.”
“Oh my, without the Republic Fleet we’re doomed!”
Any senator would do, but it might be neat to have the Chancellor of the New Republic speak before he’s incinerated.
JEDIT: Or perhaps, since we’re cutting several shots out of the Starkiller firing sequence, we could fill those gaps with the aforementioned receival of the Chancellor’s message. The sounds at the Resistance base could be muted and slowed down, as everyone listens to the last words from the Hosnian system. The speech could then overlap the shots of the system being destroyed, and be something particularly gut wrenching like ‘I have complete faith in your Resistance, and in you, your highness’.