Domain hosting and cname changes

I changed from Verizon to Comcast Business Service last month.  I have my own Domain but cannot change the cname alias inorder to verify domain ownership to Comcast.

Verizon has hosted my domain for over 10 years.  Verizon does not provide a DNS management to its customers.  I have spent hours speaking with verizon represenatives and exchanged dozens of email attempting to make the cname change.  My account with verizon is a legacy account because of it age and my domain is hosted on either:

HOME1.BELLATLANTIC.NET

WORLD1.BELLATLANIC.NET

NSDC.BELLANTIC.NET

After several weeks I finally reached the correct Verizon department, Web-support, which I believe is in India.

They agreed to make the cname change but required my "U number", whic allegedly was provide to me when the account was first opened (10 years ago).  If so, I have lost it and no one at Verizon seems to know how I can obtain it.

My hosting with Verizon runs until February 2014 (cost is less than $15.00 per year).  My email continues to work and I assume will work as long as I renew the hosting with Verizon.

Is there some way to move my hosting, either now or when the current hosting with Verizon expires,  to Comcast, without Verizon's participation?  Verizon is not my Registered Service Provider or Registrar of record.