[wp-forums] Can you help me figure out this odd WP error?

[ConstructiveGrowth.net WordPress Plugin Development]

Hello Admins,

I apologize if this is not the usual conversation on this tread.  I 
tried to ask the community for help but got back only one reply 
(http://wordpress.org/support/topic/odd-errors-can-you-help-me-diagnose). And 
now the company president has asked me to contact "official WordPress 
people" about this or I wouldn't be doing this...

I have put up a page of replies I have gotten so far from my friends and 
associates:  http://trishah.com/clients/powerdisc/error/

*Background*
I moved a client from Joomla to WP.  When the owners of the company 
access the WP site and use the top nav menu to move around, the sitemap 
shows up for a couple of seconds and then they go to the page.

I was using [wp-realtime-sitemap] but I have since deleted the software 
so all that is on the sitemap page now is the shortcode. I'm leaving 
that page on the site until we figure this out.

So first you are going to say that this is caching on their computers.  
It's happening on several computer using different operating systems, 
different browsers, and different ISPs, and on browsers they've never 
used to access the site before.  The people having the problem are the 
company owners and their friends and family in Nevada and California.  
As far as I can tell right now it is ONLY happening for the owners of 
the company and their families.

I have called Cox techs in Nevada, HostGator techs in Texas, Optimum 
techs in New Jersey... none of they can see or reproduce the problem the 
company owners are having.

Can you please access the website yourself and tell me if any of you can 
reproduce this problem?

http://powerdisc.com or http://www.powerdisc.com

Trishah