Well , judder and slip can be separate issues but can happen together . Judder is sometimes related to oil contamination of the friction plate , broken springs in either friction or pressure plate . I would rule out the flywheel as it is solid and not dual mass . Slipping depending on the severity should occur in all gears . If you put the car in third and try to pull away from a stand still , a good clutch should stall the engine . As always it's not easy to diagnose a fault from a distance !