I buy it from a close by farm where they are doing pasture farming and are involved in carbon sequestration
I feel compelled (regretfully) to inform you that unless the farm you buy your beef from is taking a loss on the sale of the beef to compensate for the methane emissions, their operation is still carbon positive and likely requires even more land than conventional techniques, which could otherwise be used for more carbon sequestration via cover-cropping without grazing those cover crops.
Unfortunately, unless you're grazing especially fertile patches of north american praries, holistic management/regenerative farming is typically greenwashing
I was going to say something more serious, but I really only want to remark that it's kind of weird you care so much about this corner case.