The textbook "Solar System Dynamics" discusses orbital inclination oscillations by finding approximated analytical solutions. At least with them I could check my simulation results which seem to be fine. Ephemerides simulations are available but their valid time spans seem to be far too short...
I did correspondence studying while working long time ago. It is possible but very hard work if you don't want to take ages. You must also be able to do self-studying -- some struggle with this. In the end, qualifications are mostly beneficial, if it is in your field of interest and applicable.
It seems that the orbital inclination oscillations of all the planets in our solar system are not well published. I've done some simulation work on this but can't find many publications to check my findings against.