Congratulations on getting that piece of flooring out. Looks great.
What diagnostics have you done? Drain issues are commonly one or more of the various filter screens in the machine.
There might be a large, fine screen that is visible with the door open and the racks out. Don't worry too much about this one. There is another one down inside, driven by the motor. This one is part of the food chopper, and it is supposed to prevent anything that the chopper doesn't grind up from getting into the drain hose. Over time, food and other stuff that got into the dishwasher that the grinder can't grind accumulates and clogs things up, so they need to be cleaned periodically. Sometimes they are accessible from inside the tub, other types require the motor/pump/grinder assembly needs to be taken out to clean it.
Look at post 644 in this thread:
https://forums.pelicanparts.com/off-topic-discussions/1023147-continuing-thread-what-you-fix-iting-today-33.html#post11139205