Zodwa's father is an asshole, "promise to marry mom, get her pregnant, and disappear" flavor. He was a decade older than her, so they hadn't overlapped at school at all, and he lied about his name and which enclave he was from, so Mom couldn't find him to make him make good on his promises. She gave Zodwa the fake surname anyway, it was easier to pretend he was a deadbeat who left her after Zodwa was born, which was easier to get sympathy for. Most people in Cape Town weren't hard sells on "deadbeat white guy leaves his black wife out to dry", inside the enclave or out.
Mom was Nontle Mthembu, a maintenance kid in her generation, and probably should have known better, but "Martin Smith" was charming and she liked the idea of getting swept off her feet and taken away to an enclave where she wouldn't just be a maintenance woman and their kids would all get into the Scholomance. She wouldn't have risked the kid without that ticket, because she doesn't earn a promised slot until she's been working maintenance thirty years and when she met Martin she'd only worked twelve. Cape Town can send a few a year, most of their kids, but not everyone, so Zodwa will be protected in the enclave with other less-favored children and she'll be able to spend adulthood there if she lives, but she won't get the school education and she won't get the school survival rates either. So Nontle wheels and deals, gets a cheap diviner to tell Zodwa her affinity ("Minds", she says, which is mostly correct.) and argues that she'll be an asset to the enclave kids, and works out a trade. They'll give Zodwa the slot in her year they'd otherwise give an indie, she'll be an enclave kid with a power sharer (and that's the important thing) but she'll be doing maintenance and she won't have it as good as the others in minor ways.
But that wasn't Mom's only scheme. She knew now that Martin was a liar, but she was pretty sure he was an enclaver and was a Brit. He said Edinburgh, and they had no one named Martin and didn't remember anyone like him, but she did slowly reach out to other UK enclavers - maintenance kids she knew from school, then their contacts, then theirs - and made time for a couple business trips to UK, and slowly tracked him down. She had a couple photos of them together, and when Zodwa was twelve, she finally found him. And, very politely, blackmailed him to arrange their daughter a Scholomance spot, no strings attached, or else she'd make sure his fiance and everyone in his family knew all the gory details and any other ones she felt like making up to make it worse. He blustered and roared, but when it reached six months to Zodwa's induction day, she says put up or shut up, and he caved like a cheap tent in less than a week.
So, deal's off, Zodwa's not on the hook - but they don't have time to find a replacement this year, they're annoyed, so she's going to have to do some, backing up her clavemates when they get dangerous assignments all four years - but now Mom's getting concessions for it rather than giving them. (And more, because while she loves Zodwa, she has been entirely soured on marriage and motherhood and is happy to trade away the slot she's promised five years out, she'll earn another in another twenty years and maybe by then she'll have changed her mind but it's not going to be sooner.)
So a muscled beanpole of a mixed-race girl shows up on induction day kitted out like a somewhat richer enclaver. She's fluent in English and Afrikaans and the cape patois, conversational in Xhosa (courtesy of Nontle's cultural backlash against the deadbeat colonizer dad), and she's spell-competent in Church Latin and Quranic Arabic. She has a well-enchanted knife so long it's almost a sword, three nicely enchanted outfits that repel all fluids including oozes, and some healing cookies she won't have to share. She has her power sharer, but Cape Town isn't always flush with mana, so Mom wanted her to have a little personal storage - and conveniently, Nontle visited Gwen Higgins as long as she was in Wales, and Gwen gave her a Radiant Mind crystal (which is beautiful, really, Zodwa would use it as decoration even if it wasn't the best in the world). She also has some tools Mom made, the lightest ones she could recreate from her time as a maintenance kid; a sawblade that cuts cleanly and makes it easier to mend-and-make the cut back together, as long as you don't wait too long (for when you need to open something up to fix it) and a wrench that can keep pushing after you let go (so you can stand back and be ready for mals) and a ruler which is a little harder to forget what you read, but more importantly won't ever misbehave on her.
She hasn't gotten anything particularly useful in her affinity to work yet; she has a simple spell to count the number of minds within five meters, which would be more useful if there weren't a dozen dorm rooms within a five meter radius of her bed. She's in good shape to fight, though, and it does count mals so she'll be able to affect mals eventually.
She takes some of the letters and hugs her mother and promises to make her proud, and fist-bumps her clavemates with a "Last one to the cafeteria gets stuck with the brussels sprouts!", and then she's yanked sideways and she's nauseous already.