[SELECT ALL] Code:
if_conline_has "you fragged teammate" [] [
if_conline_has "you gibbed teammate" [] []]
As for the other method, I agree that wildcard would be a useful tool for CubeScript, but as it stands you'll have to go the other way, using exclusions instead:
[SELECT ALL] Code:
if_conline_has "you" but_not "were" [
if_conline_has "teammate" [say HAHA SUCKA] [] []