I am guessing it would depend on the constitution of the Community.
I suspect that unless there is something within constitution which limits who you can appoint to be your proxy, then you can appoint whoever you see fit.
If you cannot attend the AGM yourself, but you want your voice heard, and your votes recorded then you must choose a proxy whom you can trust, and who shares your views.
When the AGM at our Community is held, there are people who act as proxies for a number of the members – including a management agent, who is not a member himself. Some of the members give their proxy to the chair – the rest who cannot attend simply do nothing.
If you have someone canvassing to act as a proxy, you need to understand in whose interests he is acting. On the face of it, it sounds like he is trying to get some proposal adopted or someone elected, and is trying to skew the process.