Greetings,
As you're finding out, customer service in EQ is a bit of a hit and miss affair (mainly miss, unfortunately)
GMs and Guides tend to be in-game during peak US times, so if you're not a US resident, try to be in during that time.
Petitions are held in a queue, so if you petition it still may take a while to get to you, as it winds its way up to the top.
Persistence is the key here - keep petitioning until you get an answer. Also, keep mailing through the 'Contact your GM' link at the everquestlive.com website.
Now the bad news - it is EXTREMELY unlikely that you will get your stuff back.
Not impossible, no, but very very unlikely. What is more likely to happen is that you will be given what is called a 'leg-up' kit by a GM. This is a collection of equipment and some coin (appropriate to your level) to get you going again. Unless policy has changed recently, this is what happens in 99.9% of decayed corpse situations.
Sorry to rain on your parade, but I really hope you are the exception to the rule - good luck whatever happens.