Is it possible to combine devices: bluetooth headphones + bluetooth amplifier with fiio X1 player (without bluetooth) and phone (for answering calls)?

Question

Bluetooth

So, there is available
- nexus 5 android 6.0
- Sony MDR-XB950BT bluetooth headset headset with the ability to connect via wire.
- FIIO X1 player pure 3.5mm jack.
Idea: make the headphones receive music from the player, as well as receive calls from the phone with the ability to speak.
The initial desire was to use a wire for music, so the quality is better, and bluetooth is only for calls. But headphones of this kind have a problem - when you connect the wire, bluetooth does not want to work. Another problem is that the headset only works via bluetooth: through the wire it's just headphones. But in the process of googling, it was found that the headphones have the ability to multipoint, which means you can connect two devices.
helpguide.sony.net/mdr/xb950bt/v1/ru/contents/TP00...
The next logical question is how to turn an ordinary player into a bluetooth player. As a solution, only one was found
ru.creative.com/p/sound-blaster/sound-blaster-e3
bluetooth amplifier through the jack into the player, then we connect it to the headphones via the music channel. Then we try to connect the phone for talking on another bluetooth channel.
Now the questions: firstly, has anyone tried to build a structure like this? Secondly, do you have any ideas how to achieve the result in other ways? What other ways are there to turn an ordinary player into bluetooth, 3.5mm bluetooth is not suitable because it will then be impossible to specify what type of device for the headphones. And the most important question, will my idea work? What other bluetooth amplifiers with a price of up to 10k do you know?
Thank you all for your attention.