Brother Scanner does not work with macOS Catalina
Solution 1:
"The Brother ControlCenter2 is not supported by macOS v10.15.
Use the Brother iPrint&Scan as an alternative function."
Source Brother macOS Catalina Support Statement
Control Center was a 32-bit application that Catalina wont run. Update MFC-8890 DW drivers provided at Brother website for 10.15 support.
Solution 2:
For those of you how landed here looking for a way to scan files on other Brother devices that were discontinued in Catalina (10.15+), you can verify if ICA driver is still available for your scanner and use the Image capture
built-in macOS app instead of Brother's ControlCenter.