Here's an 'eew' moment for you.
What if it is not bodily sweat that has caused this?
The human body starts to liquefy after a month of decomposing. This is known as the 3rd Stage (Active Decay) of decomposition. Fluids released through orifices indicate the beginning of active decay. Organs, muscles, and skin become liquefied. When all of the body’s soft tissue decomposes, hair, bones, cartilage, and other byproducts of decay remain. The cadaver loses the most mass during this stage.
Could someone actually have died in the chair and remained undiscovered for some time?