Thanks for all the replies! I got my unit back. Confirmed - they replaced the fusebox for an estimated cost of PhP 11k. All other parts were working just fine. Took me around 4-5 days to get it back from the casa.
Good for you Sir. Thumbs up ako dun sa naunang shops na pinuntahan mo. Hindi sila baklas agad at pinpointed na fusebox ang suspect. Dun sa casa, nabanggit mo yung fusebox o sila ang nagtroubleshoot?