Help with Modded Server

[aChickensz]

On my friend's 1.7.10 Modded Server, we crash every few minutes. The mods we use are below:

• Aroma 1997 Dimensional World
• Aroma Backup
• Dynamic Trees
• Epic Siege Mod
• Gravestone Mod
• JourneyMap
• Vic's Modern Warfare
• NotEnoughItems
• OptiFine
• Zombie Awareness
• And Every Core Necessary (I Believe)

The most people we've had on was 4-5 at once.

The server mostly crashes when there are more than one person on or we render lots of chunks.

Our server only has 3GB dedicated RAM, so that may be the cause, but we played almost all the same mods on 1.12.2 without any crashes.

The FML Log is below:

https://paste.ee/p/uxu0J (pastebin has a limit so I'm using paste.ee)

Lastly, when the server crashes, it says "Timed Out," but in the multiplayer screen and on the server hosting website (BisectHosting), it says the server is still running, yet none of us can get on untill we kill and then restart the server.

Any help will be greatly appreciated! Thank you!