Question Lenova Motherboard faulty C740-151ML

[sfunds]

I had purchased Lenova yoga model C740-151ML. purchased in US. one day while working it dropped of my lap to ground. But i was working without any problem 1/2 hr later i noticed that the battery was discharging and had only few minutes of charge. before i could close all my work and give proper shutdown the machine switched off. I tried to charge it but i couldnot. I gave to repair shop in India (I live in India) and they informed me the motherbord is faulty and motherboard is not available here. My question is 1) if Motherboard is faulty it should have stopped working immediately. But I was working in the laptop for atleast 1/2 hr 2) can i replace the motherboard if available in US 3) will the machine perform like original 3) should it be replaced by same Motherboard or or some compatible Motherboard can you suggest a way out