Things always can be traced to the secondary market. The one that used to exist was robust. The one of today is not, it is simply the GSEs. In order for a GSE to purchase a loan the originator must stick to some stringent guidelines including the hiring of an appraisal management company to get the appraiser.
It doesn’t matter if a broker knows a lender or not. Now an exception may be that the particular lender you are referring to will portfolio the loan and not sell it to a GSE. Then the rules do not apply however that is far from the norm these days.
Conceivably your broker may know the appraisal management company and can always insure they will use his appraisal pal for each listing and that the appraisal management company when they review the appraisal will always okay it then yes I guess it can happen. However your assertion is jumping through some fairly tricky hoops.
The bottom line is that it is not hard for properties to appraise anymore. Like I said the train has left the station and prices are up and moving higher faster. When the bottom fell out lenders were actually buffering in space on the low end of appraised values for many neighborhoods. Now it is opposite.
Also there is absolutely no incentive for an appraiser to make any broker happy. The appraiser gets paid no matter what. The broker CANNOT order an appraisal. The lender does and that is a phone call to an appraisal management company, that is it. The only contact is when the appraiser calls the listing agent to get access to the home. Sorry but there is no conspiracy here. Blame the policies of the government from 2007 on that prevented wholesale price reductions in real estate by manipulating the market. They won, the consumers lost. The market is running hot again with no signs of letting up.
As much as you want to push some appraisal/broker conspiracy it is not happening. At least not with loans being purchased by any GSEs.