From the surveillance video it appears that kitchen is not in service. Notice there isn't any pots & pans, kitchen utensils, tray racks for food, absolutely no food stuff in sight. And maybe that kitchen is only used when catering for large parties like wedding receptions or holiday work parties.
Yes, walk in refrigerators and freezers have door latches inside so kitchen personnel can exit.
I think once the toxicology reports are made public, that may make a difference with the direction of any lawsuits.