Why are you using the system which is meant for bigger businesses which requires a maker and checker? One man show companies normally use the banking app that is a little bit enhanced over the personal banking app. E.g. M2UBiz, HLBBiz, etc..etc..

They rather want you to purchase it via a debit or credit card instead of a bank transfer

1) I think that is where the problem lies. If your dad's business is a true enterprise, for all payments, there will be a maker and checker because different makers and checkers have a sender limit and that would have been asked upfront during the creation of the Business/Enterprise Online Banking solution. If indeed there is none, the people who will then create the account and set up the online business banking would have recommended to not use the enterprise version which requires both templates, maker, checker and many more items as those features are meant for companies that have a clear structure in there. For all sole prop and individual business owners, banks will recommend to use either the personal app version of their online banking software (which comes as a problem for some customers as they cannot run two copies of the app on a single device) or they have the biz version of the personal banking app.

2) I have to say that where Wacky Angel is coming from, you seem to have misunderstood him. Similar to him, I think trying to explain it to you is like probably swinging a bat at a brick wall.