[lolc]

The money actually comes from the employer. Employers are obliged to keep paying until the sickness is over. (The details are complicated, but this guarantee generally lasts two years from onset.) Employers have insurance against longer episodes but short-term they usually eat the cost directly. It's in the budget.

When employers suspect employees of fraud they will investigate. They can ask for a sick note but most do so only after a few days. Three days is customary. When a case is handed over to insurance, the insurance company will tend to involve its own doctors to assess the claim.

I don't understand the meaning of your story.

[sokoloff]

From what employer? Many people who need to stay home when they’re sick are the employer.

[lolc]

Indeed, self-employed cannot game the employer-pays scheme.