I've been following this, they haven't been let in for the most part. When they were let in, it sounds like it was staged.
The members of Congress said they were denied access to view the cages during their oversight visits and were told by DHS and state employees that “detainee reports of their existence and use for punitive or coercive purposes were categorically false.” “We were deceived. It is now clear that this was intended to mislead public officials at public expense,” the legislators wrote.
Read more at: https://www.miamiherald.com/news/local/immigration/article317259583.html#storylink=cpy