Switching between internal Bluetooth and external dongle?

The more I search this question, the fuzzier my brain gets...

I’m needing a way (and hoping there IS such a thing) to a quickly and easily disable/re-enable the internal Bluetooth in my mid-2012 MBP, so that an external USB/Bluetooth adapter/dongle can be recognized and used in one specific work environment. Is there any app/utility -- or an existing workflow already built in to the OS -- able to provide this kind of functionality in Yosemite (without having to run Applescripts or go into Terminal each and every time)?

I read posts about a "Bluetooth Explorer” utility from the Apple Developer site (which I am registered on, even while knowing nothing about actual software development!), but the only downloads I can find are for a same-name app by a Chris Vallis (v 3.x), the online comments for which seem to suggest does not work in Yosemite at all -- yet which is still for sale via the App Store and elsewhere with no such advisory attached.

So I would welcome any suggestions on this topic before I wander down too many dead-end paths.

Thanks,

John B