CX look at Forge's github they have a fake player for people how mod to pass to stuff when we don't have a player entity to pass you can look at that for ways to over come the problem.
This is the fake playerhttps://github.com/MinecraftForge/MinecraftForge/blob/master/src/main/java/net/minecraftforge/common/util/FakePlayer.java
This is the factory forge made for it so modders could make them this can help you make your fake player for this.https://github.com/MinecraftForge/MinecraftForge/blob/master/src/main/java/net/minecraftforge/common/util/FakePlayerFactory.java
This is the fake playerhttps://github.com/MinecraftForge/MinecraftForge/blob/master/src/main/java/net/minecraftforge/common/util/FakePlayer.java
This is the factory forge made for it so modders could make them this can help you make your fake player for this.https://github.com/MinecraftForge/MinecraftForge/blob/master/src/main/java/net/minecraftforge/common/util/FakePlayerFactory.java