Drain and Float Question

While troubleshooting my Whirlpool dishwasher’s failure to drain I lifted the float and it came out with a black washer. Does it just sit in the plastic tube or should the end be attached to something? I’m a little afraid to run a cycle it unless I’m sure the float switch will work.

As for the drain issue. Based on reviewing some other posts my first steps I guess should be to remove the drain hose and check valve to see if there are any clogs. I saw one posting that recommended pouring hot water over the pump assembly to soften any grease accumulation and then run a cycle to try and unclog. Is that worth trying before pulling the dishwasher out and removing the drain hose?

Here is your parts breakdown
Model DU943PWKB0
Has a picture of the float in the tub section. Click on the picture for alternate views.
The float switch is a overfill safety device. If too much water enters the tub, the float floats and opens a switch which disconnects the water inlet valve from power. With it removed water should not enter the unit.

Here is a tech sheet
https://www.servicematters.com/docs/wiring/Tech%20Sheet%20-%208275305.pdf

Is the motor running during a drain cycle. If not you have an electrical problem.
Clean the interior filter screens.
Remove the hose from the sink drain and let it drain into a pail. Put a towel over it so it does not splash all over. Often crud will build up at the drain fitting and eventually clog.