Question: If Callaghan knew that his daughter was dead because of project silent sparrow, how did he attended the SFIT students showcase happily? And after the fire at SFIT, everyone presumed that Callaghan was dead. So when did Callaghan visit the project silent sparrow to know that his daughter was dead, before or after the fire?
Answer: I think the fire was his original revenge plot but the microbots provided a chance for an even more satisfying end to Krei. Likely Abigail disappeared a year or two before (judging by how the men hardly aged) and Krei had to rebuild his company's image therefore creating the event. The comeback would have been hard on Callaghan and may have caused him to plan the fire and his death in the explosion assuming KreiTech couldn't recover from both, perhaps even would have taken Krei with him. But then he the microbots changed everything.
Chosen answer: The Silent Sparrow incident took place long before the events of the film. He had been plotting his revenge for some time, part of which was using the fire to steal the microbots.