Is a COMPANY responsible for a vendor they recommend?  If they
recommend someone to do a job and the vendor does not fufill, does the
COMPANY assume any reponsibility? When a company like Home Depot (not
the COMPANY referred to here) recommends a contractor to install their
products, do they assume any responsibility for the work? What if the
jobbed is messed up?  Are they at least responsible for replacing the
whole goods?

Just a free comment  - no answer:

I doubt that the company can be held responsible.  If the
recommendation was not in writing, it would be difficult to prove that
it was given; if it were, I expect that there would be a disclaimer  -
and that the company would have named a couple of contractors, making
it the customer's choice on which one did the work.

The contractor would be responsible to the customer for his own work
and any damage to the equipment installed.