I tried contacting support by chat and phone, but they are unwilling to help, saying I purchased Ring Intercom in unsupported country, although the product is sold locally?! They were not willing to get me in touch with technical person in the team nor to provide any help.

I own a Ring Intercom (with cable sets A/B/C) and want to use it with my apartment building's audio intercom. The brand and model are not listed in the Ring app, so I am sending the photos requested in your support article, plus the technical details below.

INTERCOM SYSTEM
- Original manufacturer: Xiamen Genway (China). The system is sold under local brand names: Genway WL-03-NLX in Romania, Poland, Italy and Spain and also as TEH-TEL Q2C/Q3C across south eastern Europe. Same hardware, same manuals, same programming codes.  
- Architecture: keypad door panel with RFID reader -> 4-wire digital bus (AF, DATA, GND, VCC) -> decoders (Genway WL-03NLCH), each serving up to 4 apartments.
- Handset connection: each apartment handset is connected with only TWO non-polarised wires: T&R (shared by all four handsets on the decoder) and G1-G4 (one per apartment). Ringing, two-way audio, pickup and door release all travel on that one pair.
- Handset board NE-F106-M-V1.0 is purely analogue: bridge rectifier, a few transistors, hook switch, door-release button. No microcontroller. Handset current max 20 mA, system voltage 13.5 V DC.
- The line is only powered while the apartment is being called. From the manuals and the board, the decoder recognizes "handset lifted" and "door release" from the DC load/current the handset draws on the pair.
- Ring time 30 s (call dropped if not answered), max call 120 s. Door release from the handset only works during an answered call.

TECHNICAL MANUALS

These are original technical manuals for the both Intercom systems:

https://www.genway.ro/wp-content/uploads/2025/06/Manual_NLX_V2_2021-1.pdf

https://teh-tel.rs/wp-content/uploads/2026/05/Uputsvo-Q2C-19.05.2026_compressed.pdf

WHAT I TESTED
- Generic profile, 2 wires: A-1 (COMMON) on the G wire, A-2 (SPEAKER/MIC) on T&R, connected in parallel with the existing handset. With reversed polarity nothing is detected, so this orientation is correct.
- Result: incoming calls are detected reliably and I hear the ring tone in the Ring app. When I tap Answer, the decoder does not register the pickup: the handset keeps ringing, there is no audio from the visitor, I can hear intercom ringtone in the line (this is normal as this system transmits ringtone thru same line as conversation audio). The panel times out after 30 s with "no one answered". Unlock from the app did not open the door either, which is expected because the decoder only accepts unlock during an answered call. 

MY QUESTION
Is there a profile, or a device-side setting you can apply manually (as you do for ring-to-open systems), for a two-wire handset where off-hook and door release are signaled by loading the line? If measurements would help (line voltage and current when idle, ringing, handset lifted, and with the release button pressed), please tell me which ones and I will provide them. Any tips how to make this work, I am also comfortable with soldering.

Decoder:Headset back:Headset Front:Headset closed:

Outdoor unit: