I don't know if this will help anyone but I'll share another solution I came up with that's been working well for us.
MeeAudio makes a really good quality Bluetooth transmitter that natively send to two Bluetooth speakers. It will accept mini stereo or optical digital input. If you only need two speakers connected, your all set. However, if you need more than that, you can get creative with a "switch" or splitter that allows more than one of these to be connected at the same time. I'm using an optical switch (4 in/2 out) to accomplish this. The switch even allowed you to choose with whether you output via output 1 alone, 2 alone, 1 & 2 the same simultaneously, or 1 & 2 two different streams simultaneously. So it's pretty versatile. If you need more, use a larger switch/splitter with additional MeeAudio transmitters.
Hope that helps. It's been working well for me.
MeeAudio BT Transmitter:
http
/www.amazon.com/MEE-audio-Universal-Headphone-Transmitter/dp/B016NIOOH2
Optical Switch:
http
/www.amazon.com/gp/aw/d/B00BB0GY1C/ref=mp_s_a_1_6?qid=1458356602&sr=8-6&pi=AC_SX236_SY340_FMwebp_QL65&keywords=4x2+optical+switch&dpPl=1&dpID=41UpGvjOBlL&ref=plSrch