To inform or not to inform about the presence of a disability is your right, not an obligation.
The list of documents that a citizen must provide when concluding an employment contract includes a document on the state of health (Article 24 of the Labor Code). However, it is submitted only in the case of a mandatory preliminary medical examination during employment. In all other cases, the person independently decides whether to inform the employer about the presence of disability or not.
In addition, when concluding an employment contract, it is prohibited to demand documents from persons, the submission of which is not provided for by legislation (Article 25 of the Labor Code).
If the employee did not report his or her disability, the employer is not responsible for not providing such person with employment benefits.