What is the evidence upon which your fatwa was based, stating that the emission of semen due to illness does not necessitate ghusl, as mentioned in answer number 1927?

Ghusl (definition) is obligatory upon the forceful discharge of semen with pleasure in a waking state, and upon its mere presence in a dream state. If semen is discharged without pleasure in a waking state, it does not necessitate ghusl. This is based on the Prophet's (peace be upon him) saying: "If you spurt water, then perform ghusl, but if you do not spurt, then do not perform ghusl." The signs of semen are: its forceful discharge, its smell resembling the smell of eggs when dry, or mud and pollen when wet, and the relaxation of the body after its discharge. However, the discharge of semen due to illness, injury, or lifting a heavy object does not necessitate ghusl.