I have found them on a new site,
www.goldmonacocasino.com
These details are listed, and the site itself claims to be "new", and is simply "Monaco Gold" Playtech casino. These numbers may still be current, and the site seems fully functional, but Empire are still listed as the owners.
Golden Palace seem to be part of the group too, but are owned by "Universal Spheres Inc". If these details are defunct, they should not still be taking deposits. It won't cost anything to try these phone numbers, toll free from Canada.
Support Telephone Numbers: 1-268-481-2256 (International)
1-866-463-9279 (Toll-Free US/Canada)
Fax: 1-268-481-2257 (International)
1-866-463-9281 (Toll-Free US/Canada)
Our address: P.O Box W1016,
Woods Centre, St. John's, Antigua, W.I