It's probably a result of the word's pronunciation with the short 'u' sound (e.g. 'but') as opposed to the short 'o' sound (e.g. 'not'.)
https://dictionary.cambridge.org/pronunciation/english/colombia
There's also familiarity with the Columbia Sportswear Company, British Columbia in Canada...
FIFA Rankings in our half of the draw
6 Switzerland
12 England
16 Colombia
20 Croatia
24 Sweden
70 Russia
It's coming home? Well, it's got to go somewhere...so why not?