Your question is will you maintain the current weight.
Probably not.
The HcG diet typically restricts you to 500 calories per day. Of course you will lose the weight. In the meantime, you will also be telling your metabolism "Hey, guess what? I'm not going to feed you so you'd better slooooow waaaayyy downnn and only take care of basal metabolic functions (things like breathing and cardiorespiratory activities)!" As a result, your metabolism will adjust to the stress you're placing on your body and slow down significantly, desperately holding on to any fat you have in your body, hoarding it because you're not feeding your metabolism.
Once you go off the diet, your metabolism will probably tell your brain in your body FEED ME! FEED ME - I don't know when she's going to starve me again! It will also hold onto fat and calories for dear life in the event you decide to dip that low ever again.
A few years back I lost 40 pounds. I lost the first 30 simply by eating right. No exercise. I journaled everything I put into my body. After, I started doing cardio and strength training. I have kept off the weight and not wrecked my metabolism because I chose to do it in a healthy way.
With maintaining weight loss there are no shortcuts. You will have to adopt a healthy nutrition and exercise plan for a lifetime. Yes, you can have cheat meals occasionally but they must be the exception and not the norm. Yes, this is a conscious decision to CHANGE your lifestyle FOREVER. You want to have energy, you want to feel good about yourself, you want to cut your medical costs, you want to be there for your children and be a good role model. So...it is worth it to live a healthy life.
You will NOT be able to maintain your current weight after doing the hCG diet (or any other fad diet) if you return to your old habits. If that were true, we would not have a nation of obese people, now would we?