Dangerous in-laws house

Ive posted about this before and thought that we had a great discussion with my in-laws who are hoarders about making their home safe for our son. However, this weekend we went to visit and the house was a disaster again. My son at some point was chewing on a plastic bag with an unknown pill in it that he found on the floor, and at another point was running around with a pair of scissors. My MIL acts like it’s no big deal and my husband is completely over talking to them about it because they truly dont care that their house is in the state it’s in.

I don’t feel safe taking my son there anymore but my husband is upset over this. If my son had ingested that pill, tripped with the scissors in his hand, or gotten into any of the other mysterious piles of crap around their house he could have been seriously sick or injured. So here’s my question: how do I enforce this and would it be appropriate for me to now talk directly with my in-laws instead of just my husband talking to them?