CCG3PA CC bootloader is similar process of Alternate Mode. After power negotiation, DFP will check some information which defined by Cypress CC bootloader. From the message you shows up, the response of GET_MODE VDM is not acked. I would like to recommend you:
1. Check whether the Firmware on CCG4 (CY4532 base board) is correct.
2. Make sure CCG3PA have correct power output (5V on VBUS) with bootloader mode.
3. Make sure the #define CCG_BOOT_LOADER_LAST_ROW is not changed. If you have changed, you need make sure the Bootloader project and application project have same value.
Where do I find the #define CCG_BOOT_LOADER_LAST_ROW?
Also, where is the bootloader project referenced in the application project?
I am not sure which firmware example project you are referring to. But all of CCG3PA firmware structure is same, for example, you opened firmware project - CYPD3175-24LQXQ_pa_direct_fb with PSoC Creator IDE (PSoC Creator 4.2).
The firmware structure is:
CC bootloader project -- cc_src_boot
Application project -- CYPD3175-24LQXQ_pa_direct_fb
The #define CCG_BOOT_LOADER_LAST_ROW is defined in the project as below: