You still have multiple threads working on one FrameBuffer...for example:
02-02 22:30:31.870: I/jPCT-AE(20638): New texture's id is: 1
02-02 22:30:31.870: I/jPCT-AE(20638): New texture uploaded: com.threed.jpct.Texture@40762808 in thread Thread[GLThread 32,5,main]
02-02 22:30:31.870: I/jPCT-AE(20638): Additional visibility list (2) created with size: 512
02-02 22:30:31.930: I/jPCT-AE(20638): New texture's id is: 32
02-02 22:30:31.930: I/jPCT-AE(20638): New texture uploaded: com.threed.jpct.Texture@407068a8 in thread Thread[GLThread 12,5,main]
[GLThread 12,5,main] is the older one from above and [GLThread 32,5,main] the new one, which created the new FrameBuffer. I don't know how you are preventing one of the threads from drawing, but obviously, it doesn't work. At least not in all cases. In addition, even when doing so, i strongly suggest to use one FrameBuffer per thread or otherwise, you are happily mixing contexts with unknown consequences...