Taxability of medical reimbursement by employer paid to legal heir post death of employee.

My mother underwent medical treatment for Interstitial Lung Disease at a private hospital and later expired on 26-01-2020. A proportion of her hospital bills was reimbursed by her employer and it was paid to me post her death in FY22. Is the amount taxable in my hands?

Can I claim tax exemption based on Rule 3A?