Hello, gedskii, and welcome to English Forums. Thank you for registering as a member. BrE and AmE both use 'can't have seen' (or 'couldn't have seen') in that sentence, I believe.
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Mister Micawber'Couldn't see' there would be a present conditional verb form,It can be interpreted as a past-tense form, meaning 'wasn't/weren't able to'. This works if we take 'so' to mean 'that is why'. If that were the intended meaning, I would add 'and' before 'so'.