She will face consequences, and the Silent Mystic will warn her as such: showing her abilities publicly, even if using them for good, is likely to gain the attention of unsavory individuals. He will encourage her to join the Alliance, but he won't push too hard. Just let her know that: if she does help, if she continues to not align herself with one of the guilds, she's likely to find herself in a situation where she's no longer given the choice of what to do with her metahuman abilities. The guilds will ensure she has that choice, and provide protections therein.