You can call the lender. Think of it like this. Anyone that the realtor talks to, you talk to. Also one thing that I did was every time I made a call to the lender I logged it, got the employees name and number and would send it to my clients. I did this more for my own protection then anything. There were times where I sent faxes into the lender 4 and 5 times before they somehow, “found” what I was trying to send them.
Your realtor should have passed on to you a list of items that the short sale lender has demanded. I would hope that this entire package accompanied the offer that was sent in.
As you are very early in the process, what you should be assigned a negotiator HOWEVER a negotiator probably will not be assigned until that package is complete. Now there is NOTHING from stopping you from calling your lender or servicing organization and checking on how things are going. Did they receive the ENTIRE package, when was the last time your realtor called them, has it been assigned a negotiator, if not when… etc…