It should be possible to connect the IO Pi Plus to the I2C port on the hyperpixel display.
You will need to connect the 3V3 to pin 1 on the IO Pi 40 pin GPIO header, SDA to pin 3, SCL to pin 5 and GND to pin 6. You will also need to find a 5V supply from the Raspberry Pi and connect that to either pin 2 on the GPIO header or the 5V on the 2 pin header.
The software libraries for the IO Pi Plus look for the board on i2c-1 so you will need either need to modify the library to look for i2c-3 or create a symlink from i2c-3 to i2c-1 using the following command.
sudo ln -s /dev/i2c-3 /dev/i2c-1