I have a small board with a defective memory chip. I can either send it back to Ukraine to the manufacturer and they will perform the chip swap, or have them send me the replacement chip and find a way to get the new chip on myself.

I've soldered many a motherboard capacitor to resurrect dead hardware and done many other (comparably easy) projects, but have no experience reflowing or reworking tiny 100+ pin millipede chips :)

Do you know anywhere here in the Bay Area who are able to do it and might be willing to help me with this one off?

The board is only worth around $200USD originally. The bigger concern is sending it to Ukraine and back will take many months, or cost more than it's worth.