problems with DF2301Q and ESP32

I have a few DF2301Q-EN modules. I know that they work, because I've tested them with Uno3 on I2C with I/O expansion shield. Connecting it with ESP32 is a different matter. I've used ESP32 for many years, it's a dev board that's very familiar to me. 

The sample code on https://wiki.dfrobot.com/SKU_SEN0539-EN_Gravity_Voice_Recognition_Module_I2C_UART just doesn't work on ESP32.

The I2C code from wiki compiles and uploaded but causes panic:

"18:26:56.306 -> rst:0x8 (TG1WDT_SYS_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)

18:26:56.306 -> configsip: 0, SPIWP:0xee

18:26:56.306 -> clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00

18:26:56.350 -> mode:DIO, clock div:1

18:26:56.350 -> load:0x3fff0030,len:1448

18:26:56.350 -> load:0x40078000,len:14844

18:26:56.350 -> ho 0 tail 12 room 4

18:26:56.350 -> load:0x40080400,len:4

18:26:56.350 -> load:0x40080404,len:3356

18:26:56.350 -> entry 0x4008059c

18:26:57.429 -> ets Jul 29 2019 12:21:46"

UART sample code come up with a compilation error: "Compilation error: 'D3' was not declared in this scope; did you mean 'T3'?"

My ESP32 board is a generic “ESP32 Dev Module - Wroom 32d”, I've tried different chips that I know work. This board would run pretty much anything ESP32 do, never had compatibility issues.

Can anyone help getting sample code to work on ESP32?