I tried both the GUI and the command line, here is the command-line results:
[bluetooth]# pair 6C:**:**:**:**:**
Attempting to pair with 6C:**:**:**:**:**
[CHG] Device 6C:**:**:**:**:** Connected: yes
Failed to pair: org.bluez.Error.AuthenticationFailed
[NEW] Primary Service (Handle 0x69bd)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0006
00001801-0000-1000-8000-00805f9b34fb
Generic Attribute Profile
[NEW] Characteristic (Handle 0x2384)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0006/char0007
00002a05-0000-1000-8000-00805f9b34fb
Service Changed
[NEW] Descriptor (Handle 0xf2c4)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0006/char0007/desc0009
00002902-0000-1000-8000-00805f9b34fb
Client Characteristic Configuration
[NEW] Primary Service (Handle 0x69bd)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service000a
01000100-0000-1000-8000-009078563412
Vendor specific
[NEW] Characteristic (Handle 0x0164)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service000a/char000b
02000200-0000-1000-8000-009178563412
Vendor specific
[NEW] Descriptor (Handle 0x0d54)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service000a/char000b/desc000d
00002902-0000-1000-8000-00805f9b34fb
Client Characteristic Configuration
[NEW] Descriptor (Handle 0x14a4)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service000a/char000b/desc000e
00002901-0000-1000-8000-00805f9b34fb
Characteristic User Description
[NEW] Characteristic (Handle 0x1be4)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service000a/char000f
03000300-0000-1000-8000-009278563412
Vendor specific
[NEW] Descriptor (Handle 0x2674)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service000a/char000f/desc0011
00002901-0000-1000-8000-00805f9b34fb
Characteristic User Description
[NEW] Primary Service (Handle 0x69bd)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0012
0000fe2c-0000-1000-8000-00805f9b34fb
Google
[NEW] Characteristic (Handle 0x33d4)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0012/char0013
fe2c1234-8366-4814-8eb0-01de32100bea
Vendor specific
[NEW] Descriptor (Handle 0x3fb4)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0012/char0013/desc0015
00002902-0000-1000-8000-00805f9b34fb
Client Characteristic Configuration
[NEW] Characteristic (Handle 0x4644)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0012/char0016
fe2c1235-8366-4814-8eb0-01de32100bea
Vendor specific
[NEW] Descriptor (Handle 0x5304)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0012/char0016/desc0018
00002902-0000-1000-8000-00805f9b34fb
Client Characteristic Configuration
[NEW] Characteristic (Handle 0x5994)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0012/char0019
fe2c1236-8366-4814-8eb0-01de32100bea
Vendor specific
[NEW] Descriptor (Handle 0x6d04)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0012/char0019/desc001b
00002902-0000-1000-8000-00805f9b34fb
Client Characteristic Configuration
[NEW] Characteristic (Handle 0x7354)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0012/char001c
fe2c1237-8366-4814-8eb0-01de32100bea
Vendor specific
[NEW] Descriptor (Handle 0x7f34)
/org/bluez/hci0/dev_6C_**_**_**_**_**/service0012/char001c/desc001e
00002902-0000-1000-8000-00805f9b34fb
Client Characteristic Configuration
[CHG] Device 6C:**:**:**:**:** UUIDs: 00001800-0000-1000-8000-00805f9b34fb
[CHG] Device 6C:**:**:**:**:** UUIDs: 00001801-0000-1000-8000-00805f9b34fb
[CHG] Device 6C:**:**:**:**:** UUIDs: 0000fe2c-0000-1000-8000-00805f9b34fb
[CHG] Device 6C:**:**:**:**:** UUIDs: 01000100-0000-1000-8000-009078563412
[CHG] Device 6C:**:**:**:**:** ServicesResolved: yes
Also the GUI fails as in the following image:
