SLF4J not loading in obsfuscated client

Helping my son following up from http://www.minecraftforge.net/forum/index.php?topic=37243 and starting a new thread to discuss SLF4J classes not loading. This thread helped explain how shadowing can be done where certain packages can be renamed to avoid conflict. However now logging classes are not getting loaded correctly. Here is the error that is being thrown:

java.lang.NoClassDefFoundError: org/slf4j/LoggerFactory
at com.github.dockerjava.jaxrs.DockerCmdExecFactoryImpl.<clinit>(DockerCmdExecFactoryImpl.java:82) ~[DockerCmdExecFactoryImpl.class:?]
at com.github.dockerjava.core.DockerClientBuilder.getDefaultDockerCmdExecFactory(DockerClientBuilder.java:35) ~[DockerClientBuilder.class:?]
at com.github.dockerjava.core.DockerClientBuilder.build(DockerClientBuilder.java:47) ~[DockerClientBuilder.class:?]
at org.redfrog404.mobycraft.DockerCommands.getDockerClient(DockerCommands.java:233) ~[DockerCommands.class:?]
at org.redfrog404.mobycraft.DockerCommands.ps(DockerCommands.java:193) ~[DockerCommands.class:?]
at org.redfrog404.mobycraft.DockerCommands.func_71515_b(DockerCommands.java:110) ~[DockerCommands.class:?]
at net.minecraft.command.CommandHandler.func_175786_a(CommandHandler.java:100) [j.class:?]
at net.minecraft.command.CommandHandler.func_71556_a(CommandHandler.java:79) [j.class:?]
at net.minecraft.network.NetHandlerPlayServer.func_147361_d(NetHandlerPlayServer.java:815) [lm.class:?]
at net.minecraft.network.NetHandlerPlayServer.func_147354_a(NetHandlerPlayServer.java:794) [lm.class:?]
at net.minecraft.network.play.client.C01PacketChatMessage.func_148833_a(SourceFile:37) [ie.class:?]
at net.minecraft.network.play.client.C01PacketChatMessage.func_148833_a(SourceFile:9) [ie.class:?]
at net.minecraft.network.PacketThreadUtil$1.run(SourceFile:13) [fh$1.class:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_74]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_74]
at net.minecraft.util.Util.func_181617_a(SourceFile:44) [g.class:?]
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:660) [MinecraftServer.class:?]
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:605) [MinecraftServer.class:?]
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:152) [bpo.class:?]
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:481) [MinecraftServer.class:?]
at java.lang.Thread.run(Thread.java:745) [?:1.8.0_74]
Caused by: java.lang.ClassNotFoundException: org.slf4j.LoggerFactory
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:101) ~[launchwrapper-1.12.jar:?]
at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_74]
at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_74]
... 21 more

The entire project is at https://github.com/AdityaGupta1/mobycraft and build.gradle.

Built this as

gradlew build

and copied the

build/libs/mobycraft-1.0.jar

to the mods folder.

Any suggestions on how to fix this?

Arun