DV collections for Comcast

[Rasheedab]

I started trying to repair my credit in 2012 and had some minimal success deleting collections and then life got in the way.  I DV'd Credit Management reporting from OC Comcast Cable and they agreed to deleted references to all credit bureaus.  I didn't actually pull my credit report initially this go round but I subscribed to Quizzle which showed this account in collections still on 11/24 so I DV them again.  They replied that this account hadn't been in their office since 01/12 and that they sent notice to all 3 bureaus to remove this listing from my credit reports.  Either Equifax didn't do it or Quizzle is giving me old information.  I did eventual get my credit report as I used the dispute button on quizzle which prompts a new window for equifax where you can review your report online and enter disputes.  I wrote down info which I believed the account in question was on there but apparently I failed to pdf it because I can't locate that file.  I can't access it online at the moment either because I entered an unrelated dispute and now they are waiting on my supporting documents which I mailed.  This doesn't appear on my TU report at all.  On EX this account is listed but from a different collection agency Credit Protection Association. Their listing says reported 5/08 and last reported 10/08.  Should I bother DVing them too even though they haven't reported in 6 yrs? Is there any harm in DV old accounts since I don't want to wait a whole other year for this to age off?