Lol yes it seems your doctor is quite misinformed and you should really see another one. You can definitely try, and it's a good starting point, what ScottyB said. And if having children is a concern, then this is probably the best starting point. I will say though that some people do not achieve maximum benefit (in terms of psychological/ quality of life) from hCG alone and do so more with a combination of hCG and exogenous testosterone (injections, usually once a week usually produce good results), but the effects of this on your ability to have children isn't really well understood. Ive read of people who were able to come off testosterone and restart their production with hCG and successfully have kids, and I've heard of people who weren't able to do so, it seems it might be based on the individual. If I were you I'd go and have a sperm count done to see if it's possible for you to have children (assuming this is a concern for you), then if so, start with an hCG program to try and raise your testosterone, and who knows, you may even be able to achieve a restart since your low T seems to be due to opiate use. Try this to see how you feel and what it does for you, if you feel better you can always try to ween off and hopefully maintain increased testosterone levels due to a successful restart, which would need to be confirmed by blood testing. Or if you don't feel hCG alone is helping or helping as much as you'd like, then you could consider the combination therapy I mentioned above, after of course fully understanding the risks involved.
The one thing I always push for is to make a decision that is going to increase your quality of life, as this to me is the most important aspect- this of course needs to be done based on an educated decision, something your doctor doesn't seem to be qualified in helping you decide. But either way, first things first, you need to find a doctor who understands hormones and TRT. Then you need to discuss with them what the best plan of action is for you, and you can always use this site as a source of information to check what your doctor is telling you or use to gather information to initiate conversation or ideas with your doctor about your protocol and the reasons for what you're taking. I hope this helps you.