She had pretty decent timing when we got her to settle down and play a standard no-frills beat. The more complex stuff she's trying to do isn't like Peart-top-to-bottom drum rolls (she tried some of those too, sometimes with good timing), but more of hi-hat/snare rhythm stuff.
If you and the band want to help her progress, you can try this: If you actually like the groove she's trying to do, but she's not quite pulling it off, knock the song back 10-20 bmp and run through it with her to help her out, then if she can do it at the slower tempo, go from there and slowly bring it back up to speed over the next couple practices.
Yeah, there's a lot of "wasting precious band rehersal time" here, but you guys have to probably take that as part of taking on a new drummer. You see potential, but she's still new. You will probably have to accept that a portion of each practice will be spent helping her out, bringing her up to speed for the next year or so.

If that's worth it, awesome. If that's going to be an issue, you guys might want to look into an already "broken in" drummer.
Most people (like myself) have the luxury of working this stuff out as a teenager, in someone's garage, with band members who are equally as green on guitar and bass. You all suck and slowly, after a few years, you suck less and in the mean time nobody notices the growing pains too much. But trying to come into a band of experienced musicians, when you're new on your instrument, is always going to be tough.
Put yourself in her shoes. You start playing...I don't know... flute. And you join a band. How would you want them to approach you in the same situation?