Sure.
You stated that the mountains were always there.
You stated that the pre-flood surface of the earth was as in the "low hills" model, with just the tops of the present day mountain peaks surrounded by thick soils, which were washed away to lower altitudes by the receeding waters of the flood.
So it clear that the rocks forming those mountains are older than the flood, is it not? After all you were quite clear that they were always there.
Many of those mountains, including some of the world's highest peaks, are formed of fossiliferous sedimentary rocks. Examples include the Himalayas
http://www.geoahead.com/strati/india/index.cfm?page=himalayas_tethyan
and the Canadian Rockies
http://esw.agiweb.org/imagebank/search/lightbox2.html?ID=h2ae33
to name but two
That means that those mountain peaks have fossils within and throughout the mountains. The fossils form the very fabric of some of those mountains, most spectacularly in the case of limestones where their skeletons make up the bulk of the rock. The fossils include fossils of both marine organisms and non marine organisms, indicating that some of them lived in the sea and some of them lived on the land. There are trace fossils of organisms that lived in the sea and trace fossils of organisms that lived on the land. these are embedded within those mountains.
Most importantly, from the point of view of your model, because those mountains were always there and they formed a part of the pre-Flood landscape in your model, albeit covered or surrounded by soil, those fossils are the fossilised remains of organisms that were alive, died and were fossilised
before the flood.
That means the fossils and the rocks in which they occur in those mountains cannot be attributed to the Biblical flood. The only deposits which your model could attribute to the Biblical flood would be the reworked soils at lower altitudes.