Must I re-perform the prayers I missed after learning that puberty can be indicated by the growth of coarse pubic hair, and is it permissible for me to adopt the opinion that does not necessitate making up these prayers if the issue is one of scholarly disagreement?

If you are unsure about reaching puberty, the default assumption is that you have not reached it, and you are not required to make up (missed prayers/fasts). And whoever doubts whether they were a mature (baligh) individual at the time of Dhuhr yesterday, they are not obligated to make up Dhuhr, due to their doubt concerning its obligation.