Hello. Need some help here.

My company booked an airticket for a colleague to attend a trade fair in Shangai. A CGK <> Shanghai round trip ticket with transit in Hong Kong in mid June 2019. The ticket was booked via a local travel agent ( since it's company expenses ) and the ticket already issued. However, due to some personal reasons, this colleague of mine has to resign from our company by end of this month and she is no longer able to make the trip. Thus we have to replace her with another colleague for this trip to Shanghai. However, when contacted, CX was adamant that they cannot change the passenger name citing "security concerns". The only way is to cancel the ticket with a penalty fee and re-booked a new ticket. However, it means there is much higher cost as the original cost of the ticket is about USD300/=, the cancellation fee is USD200/= and to re-book a new ticket is USD700/=.

I will like to know if this is true and is there a way to appeal this? And whether anyone has done so before. It seems very unreasonable to me that the airline will refuse to change the passenger name before a flight if there is a valid reason to do so. I suppose our case is not the first time this happen.

Any advise from experienced CX flyers will be much appreciated. Thank you in advance.