Meanwhile if sediments are collecting somewhere else entirely such as at the bottom of the ocean far from the stack in question, they are clearly not and never will be part of the Geological Time Scale OR the Geological Column.
Yes, those depositions at the bottom of the Gulf of Mexico or the Amazon Basin will never be on top of the geologic column as represented by your pet site at the Grand Canyon, but they are certainly on top of other layers that are within the geologic column you think has ended based on diagrams. You seem to think that the Grand Canyon represents the end-all-be all of time and you are trying to make it fit into your small world. However, there are layers underneath the topmost layer in river deltas, at the bottom of the ocean, low-lying prairies, deserts, and swamps, etc. The topmost layers of the uplifted regions we currently see will eventually erode and become low lying regions with more deposition, but the current basins will continue the geologic column because they are accumulating new layers which can be added to the layers we see today and some will eventually be uplifted again. If we were not here to arrange them into neat little diagrams which can be misrepresented by small minds that haven't even seen them in person, they would still go on.
The kind you can see, yes, but not the kind you imagine, the ones you call "gaps" where you assume a layer used to be but got eroded away before the next deposited. No, those I do not believe exist.
How could a layer of exposed, lithified sediment exist without layers that used to exist on top of it (since it is lithified and all)? If the flood can arrange fossils and sediments, why do some strata columns represent more "complete" timelines, while others seem to skip time creating those "gaps?"