Interestingly, from a missional perspective, it's a tough call whether to use the culturally understood name for the highest God, or import another name (even 'God' used in English circles had new life breathed into it by missionaries). The latest policy with the Arabic translations has been to use 'Allah' for God. After all, in their frame of reference, there is no other, higher being. Thus, Allah is reintroduced to them like Paul did with the unknown God (Acts 17), explaining the true nature of what they worshipped partly in ignorance. I think in the case of witness to Muslims, this is justified.

But, that's for translation and mission. It would be ridiculous for us to adopt the name of Allah for God in our everyday worship, as rather than expanding their concept of God, it limits ours, coming with significant baggage.

Anyway, just some random thoughts on the topic! Agreed - a terrible rationale from the guy you quoted, but arguably valid in other circumstances.
 

I'm not sure if I would equate calling God 'Allah' with Paul's use of the unknown god in acts 17.

The 'unknown god' in the Greek pantheon of gods was not a specific deity and instead just a placeholder for a god or gods that had not been revealed to them yet (hence Paul was revealing God to them). So the unknown god was not thought of as having any particular attributes or being, as opposed to Allah....

The more I think about it, the more I disagree strongly with the arabic translators. Is God 'Allah' or 'Brahma' or any other of the host of false gods?...not all bridges should be crossed.