admin login not working....

I have about 10 client sites, all recently moved web hosts, and all now on their own cPanel account. 2 sites recently started acting up, where I log in with my usual admin account and I was able to log in, but I get the black admin bar at the top but no access to the back end. The problem may be about DB fields not being updated for the move, so I should also state that for the migrations I used the Snapshot plugin to move the sites.

Also since I just moved all these sites, I know they all were working after the move from the old host, because I logged in to the admin after to check things out. (at least I think I did). I have each site on the WPMUDEV Hub, so you may have some access to them already.

The two sites that are having the issue are:
africabridge.org
petersonland.com

I have tried the following fixes on at least one of them:
- used cPanel to rest the admin password
- renamed the plugins folder (no change)
- renamed the current theme folder (no change)

I have googled the situation several times, and the only suspicious thing I've seen is like what is described here:

(look for this reply:

I also had to manually update the database in two tables
1) wp_<customPrefix>_usermeta – look through the “meta_key” column and change all values to the correct prefix (it was about 10 values for me).
2) wp_<customPrefix>_options – in the “option_name” column find an entry that looks like “wp_<customPrefix>_user_roles” and change it to the correct prefix.

Once I did this it all worked again.

)

I did see the db prefix was wrong in the Petersonland as described in #1 above. And in#2 above, except in the reply this fixed the issue. For me it did not, and phpmyadmin protested that the correct “wp_<customPrefix>_user_roles” was already in use for that "option_name" column.

So now I think I found something, but not a fix yet. I can't log in to the WP admin on either site, and the africabridge.org client has noticed they can't log in either. Any ideas?