I solved the issue. According to the pinout of MDEK1001’s J10 module in the datasheet, 8=Tx and 10=Rx, Raspberry’s pinout is 8=Tx, 10=Rx and I had connected Tx -> Rx. I switched Tx->Tx and Rx->Rx and I can see the prompt with a simple:
screen /dev/ttyAMA0 115200 or miniterm /dev/ttyAMA0 115200
Perhaps a typo in the manual or I misinterpreted? The MDEK1001 manual does say to connect the USB table and open TerraTerm.