How can a person be punished for involuntary doubts about God and Islam, and would God punish and condemn to Hell a person who was unable to believe what they do not possess, especially given that the human mind is limited?

Doubt, unlike waswasah (whispering of Satan/obsessive thoughts), is not involuntary; rather, it is a hesitation between two things. A servant cannot be a believer while harboring doubt, because doubt negates certainty, which is the foundation of faith. Doubt is disbelief that condemns its perpetrator to eternal Hellfire. Minds are predisposed to receive matters of faith and to believe in their soundness due to the existence of proofs and evidence that minds accept and submit to.