Cannot access our hosted website

I cannot access our hosted website from one particular office.  The website is confirmed as up and is accessible from every location I've checked except one office.  The day before it became unavailable, our website manager uploaded a good number of files to the site in a bulk upload.  My first guess was that the host saw an attack and blocked our IP address from having access, but they say that is not the case.  Is it possible that Comcast has put a similar block in place?

I can access other sites, ping, and do traceroutes for other IP addresses, but not for our hosted website.  A traceroute to it shows this:

traceroute 45.79.82.129

Type escape sequence to abort.
Tracing the route to 45.79.82.129

 1  50.203.34.225 0 msec 0 msec 0 msec
 2  68.85.244.57 10 msec 0 msec 10 msec
 3  68.86.92.61 10 msec 10 msec 10 msec
 4  68.86.86.178 10 msec 20 msec 10 msec
 5  50.248.117.6 30 msec 10 msec 10 msec
 6  72.52.92.153 50 msec 60 msec 50 msec
 7   *  *  *
 8   *  *  *
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 30  *  *  *

Any help would be appreciated.