custom code is "0X30" and the code for power on is "0x02".
(with Nec protocol implicit.) Sounds plausible to me. IFAIK, the Yamaha converter should work- You can also use IrScrutinizer, which gives:
0000 006C 0022 0002 015B 00AD 0016 0016 0016 0016 0016 0016 0016 0016 0016 0041 0016 0041 0016 0016 0016 0016 0016 0041 0016 0041 0016 0041 0016 0041 0016 0016 0016 0016 0016 0041 0016 0041 0016 0016 0016 0041 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0016 0041 0016 0016 0016 0041 0016 0041 0016 0041 0016 0041 0016 0041 0016 0041 0016 05F7 015B 0057 0016 0E6C
so if it does not work, "this cannot happen"; you have to dig deeper; there can be many reasons.