Hi there, I have over 10 years of work experience with Linux and networking. You can't actually do this as ICMP is not set to work over proxy as ping needs a direct network connection on the IP level to do its work. A proxy works on a higher layer of the TCP/IP network model, where there is no direct access to the IP protocol.
If what you need is to do an HTTP request I am able to do that. Ping me and I will, cheers mate.