Something I think about a lot is how distressed Wilhelm must have been when Subaru fled from the whale saying he didn't want to die. I feel like he would remember (a flashback that happens in the anime) that, as a young man, before Theresia saved him, he was lying in the grass saying he didn't want to die. So, he would probably try to comfort Subaru afterwards because he understands that feeling and would like it if Subaru didn't have to feel ashamed of that scene.
There’s no fucking way that seeing his beloved not-grandson stumbling away from his fourteen-year-old enemy with all his bones broken all alone and crying out for help after damn near everyone (including Lady Crusch) had abandoned him wouldn’t completely traumatize that old man. I’m not even sure he’d be able to make that connection between Subaru and his past self, he’d likely just have a panic attack on the spot. Combine that with his astounding lack of emotional intelligence and the idea that Subaru might be ashamed of that moment may not even cross his mind at all.
There’s a reason that Wilhelm is the one who’s most adamant about stripping Subaru of his knighthood in No Refunds. This scene is the reason.