Yes. That's what a ResourceLocation represents, a domain ("mod ID") and location. You ask for new ResourceLocation("NotMyMod","SomeAsset") and you'll get it.
Of course, if you're writing a json loading system for a type of asset, I recommend looking into the JsonReloadListener system. As an example,
https://github.com/MinecraftForge/MinecraftForge/blob/d4b6540746ce5676a9a2efe24b87debb3f79dfe7/src/main/java/net/minecraftforge/common/loot/LootModifierManager.java#L38
Note that you need to register it with the MinecraftServer instance, which will require some reflection.