Here is the crash report.
crash-2020-12-17_13.04.00-fml.txt

Coincidentally just came here to report this as well. Direwolf 1.16.4 pack and I assume this was compiled for just 1.16.0. Doesn't seem to work on 1.16.4.

There isn't a dependency section in the mods.toml file which is typically required to ensure it can't be run on an unsupported version of MC.