As in the samples? I could maybe try using the original percussive organ and muted guitar. If not that, what specifically is doing it?
I think it's mostly because of the ADSR choices. For example, the Organ has a very fast decay and low sustain coupled with a relatively fast release, so it gets drown out by the other channels, which is something that doesn't happen in the original. Something similar happens with the Bell sample, though on a lesser degree. I also feel like some of the volume fades on the Strings are unnecessary and add to this "softer" feeling. And speaking of which, the fade for the last String chord is too fast compared with the original.
As additional notes: I think the Sawtooth channel could benefit from using Legato for a smoother and more accurate sound. Also, the pitch bends at the intro are somewhat off since they start right away, while in the original they have a bit of a delay (about $10 should be good enough).
Lastly, you might have included the wrong Guitar sample, since the .txt refers to MutedGuitarA.brr when there is no such file in the samples folder. There is a MutedGuitarB.brr sample, but it sounds different.
Ah... I've rambled for quite a bit, I'm sorry! It's mostly just small details since the port is already super good!