Hesitantly wonder why Lord Gernert had to be killed once he'd been disarmed.
Subtly remind Ser Gilbert that it is [Your House] he owes his gratitude.
"I will hold my report for King Stannis," Ser Gilbert says stubbornly. "It is for him to determine how to distribute Thistledowns and the lands."
Eutimio kneels before Ser Gilbert, the castellan of Storm's End. "Donnel tells me we have you to thank for our victory. I won't forget your unmatched loyalty."
Remind Ser Gilbert that both Stannis and Princess Shireen are dead.
"I am King Stannis's man," Ser Gilbert says pointedly. "His Grace has no tolerance for either treachery or weakness."