you're diagnosing the different 'problem' of the joke here. first, you accuse it of being a 'random' cutaway joke. second, you're accusing it of not having a humorous material in it and i do agree with that but it still does not help what you originally attacked it of. the maggie joke in marge on the lam and punch joke in lets were brought up by me just because of the introduction of the joke here. i didn't find the eddie scene funny, but accusing of its identity (regardless of the humorous aspect) isn't the thingThe problem is this "illustration" doesn't contain anything humorous. We can laugh at the physical humour of Lenny getting punched by Homer or the absurdity of having Homer sit at a wedding with the machine but Eddie just lying in a bed doesn't have any worth on its own. Therefore the humour has to come from not expecting to see Eddie lying in a bed.
You might think that I'm being hypocritical defending Homer at the wedding and criticising Largo's xylophone gag when they're both cases of absurd humour. Well the difference lies in the context.