Best way to tame it is to use a high lvl Blood Wyvern. Make sure the setting “Allow AI special attack” is on. Send the Blood to attack the void. Be sure to contribute in killing it. The wyvern will do most damage. But left alone it will die. Once it’s low enough, mount the Wyrm and start taming it. Saves you the burden of losing the Voidwyrm to render distance.