Only if while attending he actually prayed to the false god. But attending the service for any other reason than worship wouldn't qualify.
Sort of, but not really. He wasn't being required to go to a service, he was being required to go to an event where they was also going to be a service. The service wasn't the primary reason for him going, nor the primary reason for inviting the police.
Well no, not really. It was, literally, a "law enforcement appreciation day" held in appreciation for the work the Tulsa PD did in relation to the mosque. They also scheduled the "appreciation day" on a day when religious services would take place, not because they wanted to worship with a bunch of infidels (and certainly not to proselytize and convert any of them, since that's quite impossible according to the Qur'an anyway - which office Fields would have known had he bothered to learn anything about Muslims), but because they wanted to show the police department what they do, what they were all about, to take the opportunity to dispel misunderstandings and prejudices.
Actually that wouldn't be balanced at all. The WND piece is already slanted and very selective with it's facts and conclusions as it is. No point in going overboard with it.