The course people are polite. I put "Why do we need this Keren person?" and it got rejected, although it's a perfectly valid translation.
The solution was: "Why do we need this Caren?"
Which seems incorrect to me.
It can be 'horn', but it can also mean 'ray', 'corner' or 'fund'. For instance, a pension fund is קרן פנסיה, and the Jewish National Fund is קרן קימת לישראל.
Can it also be a foundation in a physical sense, such as the foundation of a building, or would that be a different word?
No, not at all. Buildings have יְסוֹדוֹת (from the root יסד "found, establish"), בָּסִיס is often used in a more abstract sense. קֶ֫רֶן is a specific word for financial funds and fundations of organisations, be it a special sense development of "horn" or an Akkadian loanword.