without seeing model tree in pro-e 5.0 how can i get to know whether a part was made in sheetmetal enviornment or part design enviornment?
if you are using Pro-Toolbox Use the function ProMdlSubtypeGet
If the ProMdlsubtype equals PROMDLSTYPE_PART_SHEETMETAL, you have a sheetmetal part.
otherwise try convert to sheetmetal, you can convert to sheetmetal but not from sheet to part (solid) , if you can convert to sheetmetal then it was created in solid part environment
also if model has a constant thickness it was created in sheetmetal environment