First, we don't know what is under the particle board. If it is the same maple cabinets as the others, then definitely take the particle board off and try to patch up what is left. Particle board, being made of sawdust, does not paint well. No matter how smooth you sand it, the new paint will disolve some of the surface glue and make the tiny particles stand out. So, to me, painting the particle board is not an option; you can only hope for the best under that cover.
There was a reason for putting the particle board over the cabinets and I'm afraid it is because there is something unfinishable under it. You may end up having to replace the two cabinets.