I thought the main point of the copenhagen interpretation was the instrumentalist approach. That is, the mathematical description should not be considered a description of reality but just a tool for calculating probabilities of real events. So, these supposed issues with 'conscious observers' do not apply. There is no real wavefunction and no real collapse. It's just a mathematical description.
But, even if you take a realist approach to the standard QM theory and argue that the wavefunction is real, conscious observers are still not required. It is a well known and tested fact that you do not need a conscious observer to collapse a wavefunction. Take your classical double slit experiment, put a measuring device by one of the slits to force a collapse of the wavefunction (and thus no interference pattern). Now, put a piece of tape over your measuring devices display so no conscious observer can see it. The result doesn't change.
Yes, a philosopher or someone taking the collapse notion a bit too seriously would argue that the entire system (detector, double slits, measuring device etc) is in a mixed state until the observer checks the output on the detector but that is quite a stretch. (See the whole Schrodingers Cat debate)
All measuring devices are huge from a quantum mechanical standpoint. We can barely make calculations on large objects like molecules (and that with rather heavy approximations) and measuring devices typically consist of lots and lots of molecules. It is currently quite impossible to write down a quantum mechanical description of even a simple experiment with a simple measuring device. If we could, maybe we would see that the that the addition of a measuring device causes a mixed state to evolve into a pure state, just by the laws of QM. No conscious observers would then be necessary and the 'collapse' would be just a consequence of the theory. However, making those calculations is way too complicated and far from what we can currently do.
So, neither the instrumentalist or realist interpretation of standard QM theory requires conscious observers.