Alright, so the forge loads perfectly fine on my pc and the modpack is playable in singleplayer but issues arise when I try to make the server. I've worked through some issues regarding mod conflicts and old versions but I've gotten to the point where I'm either blind or there aren't any easily noticeable error messages with the launch.
Pertinent server info
Forge Mod Loader version 7.99.40.1614 for Minecraft 1.7.10 loading
Java is OpenJDK 64-Bit Server VM, version 1.8.0_191, running on Linux:amd64:4.9.120-xxxx-std-ipv6-64, installed at /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.191.b12-1.el7_6.x86_64/jre
Pastebin of server crash log
https://pastebin.com/1ddSUJtQ