Void magic does not include healing properties. It does include creating and returning things from and to nothingness.
Thus, Kyran's purpose in inclosing the Conclave members with his magic sense was to cover their wounds and stop them from bleeding out. After that, he used one of Draconic magic's properties: body strengthening. Because he could not share his healing abilities with them unless these people were connected through a Sigil, doing this would at least help them strengthen their bodies and endure the pain.
Another reason Kyran could not maximize the use of his magic sense was that it was his first time combining the Draconic and Void magic to this extent. Before, he would only do so with a small range and only to scout his surroundings. It was his first time using them together in such a large range and actively using both magics' properties.
