Yep, he did respond to her anon post at the time when he caught those mice. So he knew that it would be brought up eventually.

“Oh yes. I am pretty certain that plenty of Pokémon would be gathering and eating loads of foods with winter approaching even closer. So I was certain that these mice were wanting to get a head start for the winter as soon as they can. I guess that several of them will going to going into hibernation season soon.”