I am really sorry to hear about the person you quoted who lost his life. In my opinion, there is no harm in deferring the allocation if one has the intention to go for it in case one doesn't improve ones group or whatever are the circumstances.

In CSA you are not allowed to reappear and majority of the candidates defer it because they want to go for next attempt to improve. In these cases it is quite justified to defer and keep the option in your hand which you earned through your hard work and with Allah's blessing.