Yes, I know they are only for burning Ironite and that they are (only slightly) worth only if their give trooper frags, too.
That's why I didn't buy them willingly. But since the purchase have been half summoned already, NF refused to reverse the purchase and return me the Ironite. With some positive reference on dropping the highlighted characters and/or talismans, I hoped I might get actually lucky this time.
Didn't happen - as always
I need to better remember already in the past learnt rule I set to myself - never again buy banner or event souls. Only exception - only if I know I have enough Ironite to earn the event characters via event frags.