Complex sentence: It seems that Ayyanar and his friends (the workers) replaced the temple jewelry with fake ones and Selvi found it out using her prediction powers and confronted them, so they killed her and buried her inside the palace when she came to meet Murali.
Split into simpler sentences: It seems that Ayyanar and his friends (the workers) replaced the temple jewelry with fake ones and Selvi found it out using her premonition and confronted them. So they killed her and buried her inside the palace when she came to meet Murali.