My dishwasher leaked in the night of Aug 1, the water went down into the basement ceiling, and went out to the exterior on top of the basement window. I noticed the leak the next morning. There might be water leak before I bought this house one year ago, but I'm not sure.
Multiple fans are now being used to dry the cabinet and the structures in the ceiling, 3 50-pint dehumidifiers and one AC are used to dehumidify the basement room (RH 35%), and one air purifier to reduce the dust in the air.
I wonder if I can DIY the water mitigation or I must hire some professional. My goal is to prevent structural damage and mold. Is air dry enough? Is desiccant needed? I saw somewhere on YouTube a spray is applied after drying. Is it necessary? What spray I shall use?
Here are some photos.
Where dishwasher was installed. Right side is slightly lower than the left.

Inside of the basement ceiling, around dishwasher, from right to left










