Hi, Momof5, I feel your pain. I've been getting ready to try to get a medical collection off my husband's reports, and I'm dreading it.
It sounds like what you're facing is the typical crappy reporting by collection agencies, compounded by lazy, sloppy work by the CRA's. The problem for your scores is that they are driven by the info on your reports. FICO creates the scoring formulas used by the CRA's (and they each requested a different one.) These formulas crunch numbers. If the numbers furnished by the CRA's are incorrect, the resulting scores are affected. So the anger needs to be aimed at the CA's and CRA's, who are responsible for what appears on your reports.
Congrats on getting the one baddie off your EQ, and I'm sorry to hear about the other. Your situation shows why most people don't try to fix things that are ready to fall off. Collection agencies get worried when they see that the collection won't be showing (and hurting) much longer, so they love a chance to change all the dates around.
I'm just now starting to learn about collections, so I know just enough to be dangerous, but it sounds like the CA has done something wrong. You might want to post the exact details over on the General Credit board, and see if someone much more knowledgeable than I can offer some help. In the meantime, I have to take time this weekend to learn the process myself.
BTW, none of the moderators here are paid. (I wish!) I work in health information for the federal government in my day job, and in my part-time job, I do the same for a contractor. I think myFICO figured that since I seem to read every single post and reply to many of them, they might as well make me a mod and get something useful out of me!

--hauling (mom of 3)
* Credit is a wonderful servant, but a terrible master. * Who's the boss --you or your credit?
FICO's: EQ 781 - TU 793 - EX 779 (from PSECU) - Done credit hunting; having fun with credit gardening. - EQ 590 on 5/14/2007