gsm shield 2, M10E-04-NCH-STD, serial connection 2(debug) and 3(UART)

Hello everyone,

i have a question about the M10 modem (quectel) on the Arduino GSM Shield 2. If I follow the documentation, there must be 3 serial ports (UART). The first is the usual serial port, which is connected to the shield and described as "GSM TX and GSM RX" on pins 2 and 3.

I can create a PPP connection OR send AT-Commands through it (NOT both at the same time). That's why i want to to use both serial ports. One to create a PPP-Connection and one to send AT-Commands.

Now my question:

If I want to use the other serial port, which isn't connected, I have to solder directly on the Quectel-modem (pin 62, 63). But I receive nothing.
What I'm doing wrong?

Second question:

Does anyone tried yet to read the debug pins (DTX, DRX) on the backside of the board? If I try to do this (with Baudrate 460800, as described in the docs), I don't get any useful data. Just something unreadable.
Do I forget about something?

I appreciate your help!!

Thanks in advance!