Mexican Black Kingsnake not eating

I've taken in my friends baby mexican black. My friend got her in late August at an expo so she's around 3 months. The breeder said she was eating fine on live pinkies though we're sketch about it. She has never eaten for my friend who has offered only f/t but she has shed once. We have brained the mice, made sure they are warm, scented with fish and chicken, tried putting her in an empty tank with it, left it over night in her tank and nothing. I own two ball pythons and am familiar with assist feeding so I attempted this with no luck. She will open her mouth fine and lets me get the head down her throat a little bit but as soon as I set her down she spits it out. Any suggestions aside from just trying live? I'm concerned she's too small for for a pinkie, it feels like it's just too big when I tried to assist feed. She will close her mouth around it and get her teeth in but still can't seem to get it down, it just won't go past her jaw. Pictures included.

http://i1146.photobucket.com/albums/...pszfjjjsmj.jpg

http://i1146.photobucket.com/albums/...ps1mkckd3c.jpg

You'd be surprised what it could handle. Pinks would probably work just fine for it. She's larger than one of my new animals, and that one took a pink just fine.

If the seller said it eats live, the best solution would be to try live. Another trick would be to put it in a small deli cup with the prey and cover the deli cup. I have a few tricky feeders who will only take food that way.

I know that kings can be snake-eaters in the wild, so you could probably also scent the food by rubbing it against another snake or reptile before presenting it to her.