It's a hard problem in a way. If my language is localized to English, am I more likely to understand the native pronunciation of a street, or the English mispronunciation?
I don't understand if you're presenting this question broadly, in a vacuum? Or if you're still in the context of your question about (mis-)pronunciation of streets etc. while providing navigation for a driver whose chosen language is not the same language as the current location, and who it may be safe to assume cannot understand the local languages' pronunciation even when the alphabet is similar (e.g. an English speaker in a Portuguese speaking country is very unlikely to understand if the navigayor natively pronounces "rua da Heitor do Rio do Engenho", a name I just made up that may exist somewhere, which I think demonstrates the difficulty I'm talking about.)
(The German Michael is kinda... Michh-aye-ehl'.)