The phrase "went one's reward" is a euphemistic way of saying that somebody has passed away or died. It is often used in a respectful manner to convey sympathy and condolences for the loss of an individual. However, there are many other synonyms that can be used to express the same sentiment.
Some other popular expressions and phrases that are synonymous with "went one's reward" include "passed away," "departed," "rested in peace," "gone to heaven," "met their maker," "expired," "breathed their last," "left us," and "ceased to be." Each of these phrases can be used to convey a different level of solemnity, depending on the context of the situation.