She'll be okay - i've had a portion of my tongue removed, and was eating soft foods within 9 days (not sure why they pegged her... Usually that's reserved for radiation as its more long term ) - her healing period may take longer as she's had radiation only a short time ago. But I suppose they're being cautious. I'm assuming they're just removing a portion of their tongue and maybe doing a neck dissection - if that's the case - she may have some difficulty talking - and eating for bit but should recover ok - as long as she avoids infection, and doesn't have too much trouble healing.
Take care... She should be ok assuming her drs. are good etc...Give her a hug from me and tell her I'm saying a prayer for her.