cool bro, maybe he lost it somewhere he is sure nobody can pick it up.
i think theres bro here who ever lose their i-key in the beach, so the chances of kanna the person who picked it up and happen to open your car quite rare, like strike 4d.
for me, i also misplaced my mechanical spare key, quite sure it is in my house somewhere but just can't find it.

i ever called up soxxi, located in toh guan to enquire, they are able to do it, quite expensive but they are giving original nissan keys, cost about $180 to do up a spare mechanical key + reprogram my current i-key. takes about 30 minutes to 45 minutes.
TCM quoted me $200 for the same thing, need to go down twice, one time to copy your codes and the next day to give you replacement key.
actually, i also suspect TCM may just outsource to outside companies to do it, thats why need 2 days.