APEX nx400 watt MOSFET AMPLIFIER BOARD. DIY, pcb print mistake problem

in this video you will see a subscriber has purchased PCB from local PCB supplier of Apex audio board but during the editing of top Silk of this PCB the supplier has make stupid mistake by printing BC 547 in place of BC 557 .
so the subscriber was suffering from failure of the circuit and finally he sent me for finding the actual problem of this board
pdf file https://drive.google.com/folderview?id=17P96Sjw5f75tpVuDxjG5NtLxFKFFquVS