Hi Kam,
I'm with you, it's not clear why the manufacturer is selling the board "without IC". The closest analogy I can come up with is that you can buy an iPhone screen without the touch module IC specifically so you can transfer the IC from the original screen to the replacement. But I have zero information that says anything from your original charging board needs to be saved and used on a replacement.
To be honest, if it was me I'd buy the one with the IC and hold on to the original just in case. But buying the one without the IC means there's something on the board that's not going to work so I wouldn't go there personally.
I'd be curious to hear how this all turns out, so let us know what you decide and what happens with it.