try and set the LNB LO to 10750 and see what happens
Persistence compensates for lack of genius. I did more testing in search of the elusive ITC signal on 11898.
The 11898 signal mixes with 11250 LO in LNB and produces an IF of 648 MHz. My Coolsat receiver LO setting of 10750 adds to IF of 648 MHz and should produce the received signal at 11398. But...a 12399 signal also coming into the LNB from another transponder produces an IF of 1149 MHz. This signal adds to receiver LO of 10750 producing 11899 and that is what actually gets scanned into the Coolsat instead. I checked 11398 but no signal there. I am receiving all the 12399 stations labeled 11898. Of course they are all scrambled.
I have my S9 input connected to the IF from the back of my Coolsat. I have another chance to get 11898. The 648 MHz IF enters my S9. If I set my S9 LO to 11250, this produces a signal on 11898. I scan this 11898 signal. The result is stations from the 12020 transponder. This is because the 12020 signal produces an IF of 770 MHz. The 11250 setting on the S9 LO results in the 12020 stations (770 + 11250 = 12020) being scanned in when I scan 11898.
I try again setting the S9 LO to 11200. Same result as for S9 LO of 11250. I try again setting S9 LO to 11050. No signal appears at 11898, but a signal appears at 11698. The scanned result is the same 12020 tp stations (770 + 11050 = 11820). I set the S9 LO to 10750, this produces a signal on 11898. I scan this 11898 signal. The result is stations from the 12399 transponder just like on the Coolsat, plus an extra 11 stations from somewhere (can't find their SIDs anywhere in documentation).
With these 12399 plus mystery 11 stations scanned in, I reset the S9 LO to 11250. The info screens for some of these indicate ITC channels. But no video since the receiver seems to know that some of these stations should be ITC, but the signals are not the correct signals.
I switched the roles of the Coolsat and S9 with the S9 controlling the LNB and Coolsat being slaved. Nothing significant found. The Coolsat nicely labels stations found with station name in text, so that's friendlier, but the S9 seems more liberal in seeing and scanning stations regardless which LO frequency is selected.
Bottom line: I can't trick these receivers; they are smarter than me. I guess I have to buy a wideband circular LNB as suggested by Pixl.