Ayurveda is a system of healing that involves multiple modalities including diet, use of herbs and supplements, and even enemas. There are no published studies suggesting that any Ayurvedic treatment will "boost" kidney function and in fact any "cleanse" can be harmful if kidney function is low, because of effects on the salts in the blood called electrolytes (like potassium or magnesium). That being said, dietary approaches that include vegetarianism or veganism, which are part of Ayurveda have been shown to prevent worsening of kidney function in some cases, and help with high blood pressure and diabetes control. Also, massage may lower blood pressure, as may meditation by reducing stress hormones, and lower blood pressure helps preserve kidney function.
So, the answer is that I do recommend certain parts of the Ayurvedic tradition including massage, meditation and plant based eating, but I do NOT recommend herbal supplements (except on an individual basis in discussion with a physician) or cleanses. And there is no therapy at this time that will "boost" kidney function, only keep it from getting worse for a time.