Ah I have the same questions and come looking for answers!
Based on my findings (there is a page in github created by some former or current vmware employees), the cash portion needs to be reported fully as taxable income (capital gain) according to form 8937 (it's lesser than Cash+FMV AVGO - VMW cost basis. The VMW cost basis becomes the AVGO share cost basis (VMW total cost/AVGO quantity you received). And the 15% ESPP discount will be reported as ordinary income in the future when you sell AVGO shares.
I honestly don't understand the cash portion being fully taxable. Didn't I pay to buy the VMW ESPP? Same as my RSU, I already paid tax on them when they were vested.
