Hi,
thanks for the extra explanation. It's clear now.
The issue you're having looks the same like the one in this post
http://www.dvbdream.org/forum/viewtopic.php?t=2552
Have you tried to add the transponder manually to the existing satellite on 28? I don't know this for sure but, I know there can be more than 1 satellite at a position (0192, 0235, 0282), but does your dish/software know this? they just receive all the 'streams' the satellites on that location are transponding, tuning into a frequency of a specific transponder.
I've added a transponder from a satellite which wasn't available in DD (but was on the same location, 0192) and added this one to the existing satellite which was available in DD. scanned it, and it just worked.
Now, I'm still no sat-expert, and I'm still learning every day (interesting hobby it is), and if you look at some sat-freq-websites, you'll see that no more than 1 satellite on a specific fixed (same) location will send out a specific frequency on their transponders (like on 0192 1M is transmitting 10714.25 H, none of the other satellites on that position have transponders transmitting on that frequency)
If someone is reading and I'm not correct... please tell so, so that I (and we) can learn some more.
(edit)
btw.. diseqc is not only needed for moving dishes (rotor) but also in multi-lnb-setups where you need a switch (like you have more than one (fixed) satellite (=lnb with cable), while your pc-sat-card has only one input.
like, lnb are 'viewing' a satellite, you add a satellite to (multiple) lnb ('s) in the menu: Menu->options-Diseqc. .
There you've switch type.. if you choose one, you can only add one satellite (=location).. depending on the switch type, you should be able to add a total of 16 lnb's (= positions, =satellite locations, 0192, 0235, 0282)
Hope this helps