Russell nods along absently to the point about the letter. They couldn't work with mouse-sized writing, too likely to be illegible. But maybe they could compromise at something like cat-sized...? A little trouble for the mice to write, but he'd need a camera to help him read it, that's sort of fair. As long as mouse scratches aren't like chicken scratches.

"Is that right... They might be full of it," he cautions, as he gives up on tugging at the grate. He's unsure of that even as he says it - he remembers hearing similar boasts in his own school days, but he never checked into whether any of them were true.

But that's not the biggest issue here - he is. He pointedly straightens to a height nearly half a meter taller than Nel, and smiles lopsidedly. "Or there might be a tunnel you can get in... But can I?"