I would first talk to the Verizon Business account reps, and find out what types of accounts are able to be incorporated with an "assumption of liability" - or if this is even doable on a business account. If you can do an assumption of liability, THEN read the fine print on your Amazon wireless contract. It may constitute a plan change and trigger an ETF or other fee; it may not do anything past the 181 days....
Bus rep not much help. All he could tell me is that an "assumption of liabilty" is not a termination so at least from Verizon's end there would not be early temination fees. OK - and that sounds as if you CAN do an AOL on a business account.
Amazon had no clue what could happen at their end. Look at the contract then - see if there is a clause anywhere in there about changing plans or changing service options within the first 6 months, or 3 months, or whatever time frame. And it sounds like you are already beyond that time frame anyway, so it may be irrelevant.
Then go to Verizon, and proceed with AOL to add the line to your business account, if there doesn't seem to be any language in the Amazon contract to discourage you from doing so...