How would you go about achieving these string and percussion sounds and dark tone?

The Serinator

I am Groot
I am obsessive over little details like this and have failed in my many attempts at experimenting my way into the answers, so I'm hoping someone with a little more knowledge can share some wisdom. :)

Overall, I'm happy with the mockup I posted in the member compositions forum, but there are a few niggling details that are eluding me.

Libraries used are Audio Imperia Areia for strings, Jaeger/Talos for Brass, Nucleus for percussion and choir.

Super short aggressive spiccato string notes:

I have tried the following but can't seem to get it to sound quite the same:
  • Adjusting the release between 450-1.1k ms in the ADSR envelope
  • Adjusting the attack/sustain/psychoacoustics via Neutron's transient shaper, compressor, spectral sculptor and EQ
Maybe the samples used just aren't fast enough or aggressive enough?

Thunderous drum in the background:
  • I have tried using Gran Casas from Nucleus, Cerberus and Damage 2 along with the Timpani from Nucleus and a combination of layering them as well. Nucleus' 2 Gran Casas patch seems to get close, but not quite there
  • Soaking the drums above in the built-in room reverb seems to help some
  • Using Neutron 3's transient shaper to minimize the attack and boost sustain seems to help
  • Using Neutron 3's spectral sculptor with tone near maxed and applied at around 80/100 closes the gap some, but starts to get too clicky in the top-end
Overall dark tone:
I've tried rolling off mid-high and high frequencies in the EQ, but it seems to just make the sound more muffled than darker. Dr. Google hasn't been much help, but maybe I'm not using the right search terms.

Source (begins at 1:47):

My mockup: