John Oliver covered this two years ago: https://youtu.be/IhO1FcjDMV4
https://www.propublica.org/search?qss=meatpacking
I'm not sure if ProPublica has a free, public dataset on meatpacking plants but they generally have datasets that you can purchase that pertain to particular areas of reporting: Medicare and Medicaid overbilling / fraud; repeated pollution violators who keep paying fines instead of stopping polluting; etc. If anyone knows of a dataset on meatpacking plants, health and/or safety violations, etc. please do share the link to the dataset.
The argument that more pay & benefits for these workers will make meat more expensive is also nothing but a scare tactic. There is already so much automation that the increased cost will hardly be noticeable when it is distributed among purchasing units at the consumer end.