You cannot open an Accountant copy in any program other than Desktop Accountant version. https://quickbooks.intuit.com/accountants/products-solutions/accounting/desktop/
If you cannot afford the entry fee of 449/ year then your client must send younanregular QBB backup file and they must NOT make any entries whike you make any correctikns and send it back as another backup as all their interim input will be lost. That alone is why the accountant copy and change file is best scenario
You can install Accountant Plus alongside Desktop Pro by selecting advanced install. You just cannot have both programs open at same time.
If you just bought Pro you might be able to return it in exchange
