Hello Luke,
by immiseration, do you specifically mean the suppression of wage growth in order to increase value from labour time? the extent to which capitalism regulates life in order to control its reproduction, is the extent to which poetry is about immiseration if poetry is about life, or death, or written by a living person under waged conditions? the extent to which a poem looks eye to eye with these conditions - tries to, is able to, obscures itself in failing to - and tries to speak out from the language of prices - is perhaps what you gesture towards in your question.
I'm reading Tongo Eisen-Martin at the moment - some poems available online.
Edmund