.NET-Event "AssemblyResolve" only fires in Dynamics NAV on client side, not server side?

So, the setup in this issue is maybe a bit complicated. I will explain it with editted names and try to keep it simple:

I have a .NET-Assembly "Processor.dll" with a single class "Processor" that I want to make use of inside a CodeUnit in Dynamics NAV 2017.

"Processor" requires another dll "Logger", which is held inside a file "container.libz" created with - as the name suggests - LibZ.

Inside a method of "Processor" I resolve the container and load the "Logger"-Assembly. A simple Version of the Code would look like this:

In NAV CodeUnit (given that "P" is the Processor variable and "T" a text variable):

P := P.Processor;
T := P.DoStuff;
MESSAGE(T);

In the Processor class:

public Processor()
{
    Initialize(); 
    //this among other things causes LibzResolver to be initialized
}

public string DoStuff()
{
    LibzResolver.RegisterFileContainer("container.libz");
    Assembly dll = AppDomain.CurrentDomain.Load("Logger");

    //more code using the dll
    return someText;
}

The assembly is found as LibzResolver makes the container's contents known to the domain by subscribing to the AssemblyResolve Event.

So problem here is the following: This code in fact works fine in test Applications and when running the NAV CodeUnit on the client (Setting RunOnClient = Yes for "P")

When I try to run this code on server side though (Setting RunOnClient = No for "P"), the AssemblyResolve Event is not fired. As a result the dll is not found the code stops with a FileLoadException.

I checked various articles about AssemblyResolve and .NET-Assemblies in NAV, but I did not find anything that applied to my case or could be applied at all.

Does anybody have an idea what may cause this behaviour?