http://www.weblio.jp/content/%E5%AE%8C%E4%BA%86
かんりょう is the correct reading. Can't tell you why the ワンラ entry exists, but I can tell you that in general it is not necessarily always the best idea to trust the given furigana for example sentences on jisho.org if you're not sure of something. Better trust your wife, especially when it's such a common word.
jakobd, thanks for the warning. Was never sure how accurate the readings were in many cases but this was the first time I had made an inaccurate one my primary pronunciation because it makes up the bulk of the examples.
This is definitely an issue with Jisho assigning the wrong word, and thus furigana, to 完了. I have a standing todo item for making furigana more reliable, but I rarely get the time to work on it.
Btw I found out why this entry exists: https://ja.wikipedia.org/wiki/%E5%85%B5%E9%9A%8A%E3%82%B7%E3%83%8A%E8%AA%9E
Sweet, another way that Japanese text can be tricky :—D
The sentence has been moved to the かんりょう entry and now has the correct reading.
Wanra
My Japanese wife insists this isn't a Japanese word. Obviously it derives from Chinese, but she's never heard 完了pronounced "ワンラ”、only ”かんりょう.” Is this slang? Regional dialect? Just a loan word from Chinese? I noticed most of the sentences for 完了 use ワンラ in the furigana, which is why I started using it as the primary pronunciation of that kanji.