Do all Bombardier jets have manual reversion?
Can't speak for the Lear, which I believe has manual controls anyway, but the CRJs DO NOT have manual reversion.  The RJs are designed to a technical level similar to the Boeing 767.

The control surfaces are purely hydraulically operated.  For elevator and rudder, which have 3 PCUs each, you'd have to lose all 3 hydraulic systems to lose the surfaces.  For the ailerons, which are 2 PCU and split one of them on each side to Hydraulic System 2 and 3 while the others run on System 1, you have to lose 2 systems to lose one aileron, and all 3 to lose both ailerons.

The probability of this kind of multiple failure event is below the 1:1,000,000,000 risk threshold for catastrophic events, so it's good to go.

It's been discussed before how the hydraulic PCU can kind of be driven manually by hauling on the controls to lever the PCU piston about the bottomed-out servo control valve, but this would only give a bit of movement at the limits of control travel in any case and is not a practical consideration for trying to control the aircraft in flight.