The wireless variant of the ConnectCore 6UL system-on-module contains Qualcomm-Atheros chip QCA6564A, which is Bluetooth-capable. This module is built with coexistence in mind and handles the Bluetooth coexistence internally.
The Bluetooth interface is connected to the i.MX6UL via the UART1 port.
I have just made a quick test and monitor mode seems possible. I modified a DEY project to add tcpdump, connected to a wireless access point, got a DHCP address and pinged a device on the network. I then launched tcpdump with:
root@ccimx6ulsbc:~# tcpdump -c 100 -vv -i wlan0 -w /tmp/wlan0.pcap