Most Gods and spiritual gurus had suffered in their last days. Lord Krishna had a nonhealing wound, Jesus Christ was crucified, Swami Chinmayanand had low functioning heart, Maharshi Mahesh Yogi had heart and pancreatic disease, Satya Sai Baba was put on a ventilator etc.

When they were God-like personalities, why did they suffer in their last days?

The answer to this comes from Vedic knowledge within the concept of rebirth. Vedanta says that the very fact that we are born means that in the last birth we did not attain moksha or liberation. In other words, this means that there were some sufferings yet to be faced. You are born to face those sufferings. When you face the last suffering, there are high chances that that suffering may be your last suffering before liberation.

Most Gods or saints who died in a phase of suffering may mean that they did not attain liberation.

A person who dies suddenly or unnaturally would mean that he would have to take rebirth to face more sufferings.

According to me, terminal sufferings are good from spiritual point of view.

(Disclaimer: The views expressed in this write up are my own).