dont expect them to fix your issue with USD accounts. they wrote this program several years ago and they wont change it. 

I also work with multicurrency  ( CAD and USD ) on QB pro DESKTOP version ( forget ONLINE BS )  and when you write cheque or receive money in USD,  you account this in USD BUT at the end CRA and Canadian government wants to see all values in CAD ( your income and expenses ), and QB provides all thse amounts in CAD Only , when you do reports, income statements or balance sheets.  You have to use conversion ( exchange rate ) rate at the time of transaction - income or expense. 

I learned to live with this and there is no other way except opening another QB file in only USD currency and have them completely separate.