Using an end panel only, no unit, at end of a worktop?

I've got a kitchen on order and have planned to have a freestanding washing machine and dishwasher (not integrated) at the end of one of my worktop runs. I've originally planned with the kitchen company to have an end panel on the end (not attached to a unit), then washing machine behind a flush fit hinge (it's only 500mm deep) then use the remainder of the end panel in-between the freestanding appliances as support, then a corner sink unit. (Supplier is DIY-kitchens.com)
However, I'm concerned...

Using an end panel only, no unit, at end of a worktop?