I think existing answers already answer the "why" component pretty well, but there seems to be some confusion in the comments about the spelling. Long story short: the same spelling works in both languages, and there are multiple spellings because transliterating is actually pretty hard.
I only have experience in one of these languages, but transliterating English to Arabic is a messy and remarkably inconsistent process. There are many possible choices with subtle pronunciation differences. The different regional dialects of Arabic introduce even greater variation, since some letters are pronounced differently.
Personally, I wouldn't write it as كامالا and I don't think that spelling represents the vowels very well. I would write it as كماله or كامله (they stress different "a"s), and you'll notice the first one looks an awful lot like کمالہ. The letters are actually identical, even the last letter, which takes the same form (ه) when out of context in both languages. It's written differently in context because Arabic script is complex.
Letters are connected (a bit like cursive) and take different shapes depending on their placement in the word. Even in the same context, there can be more than one way to write each letter. It's also wildly diverse in handwriting styles (with a long tradition of calligraphy) so there are many different ways to stylize each version of each letter.
In standard printed Arabic كماله would be the norm, but Arabic handwriting I would expect کمالہ to be common. It's a bit like the lowercase "a" in English, where the handwritten forms use simpler strokes than a printed font.
In any case, the names are essentially written the same way in both languages. They both use the Arabic script, and while there are plenty of linguistic differences, none of them really apply here. The only (apparent) differences are superficial choices that would be valid in both languages.
It very well may have been intended to be Urdu, and that would match standard digital print more closely, but it's completely valid and recognizable in both languages.