Your Batrep mentions experience points for level difference. Is that a houserule you are using, and if so can you explain it ?
Yes, it is a house rule we are using that was inspired by a rule in Mordhiem whereby if you are fighting a warband that is much more experienced than yours you earn more experience from the encounter (from being schooled by the best!).
Basically if a wizard is fighting against a wizard of a higher level, the lower level wizard earns 10 extra experience per difference in level at the start of the game.
For example a level zero wizard fighting against a level ten wizard gets 100 extra experience. A level six wizard fighting against that same level ten wizard only gets 40 extra points.
It's a playing field leveller - for people whose wizard has died, or they joined the campaign later, or they just don't play as much as others...