The 40kHz is a modulation frequency isn't it, like an AM signal? The rate of the data being sent is lower than that, but still too high for the camera to detect.

At ~30fps, each frame lasts something like 33ms (ignoring integration and reading times), and the bit length (in time) for e.g. a Sony remote control is of the order of 2* 600µS.

See http://users.telenet.be/davshomepage/sony.htm

So no chance anyway