NB are you still having an issue:
Quick check. It sounds like you are displaying(symbolize) objects using extend Z by multiplying your AGL (above ground level) fied with a number say 100.....Easy check by going to symbology and seeing if extend Z option selected. If not then This is all in the SCENE viewer window in arcPRO 3.0>>Is your object layer a feature class 'z' value?...if not interpolate point to raster (dem). now you have x,y, z objects. All distances are meters including elevation. I'll come back to this.. just to add to DP's answer...check your feature's projection and coordinate system. If no defined projection...then reproject to a distance measurable projection, usually some type of mercator. So if large scale use UTM zone (#based on longitude + and - 3 degrees) . MAke sure your elevation and feature layers are in same projection. Try Properties ELEVATION > Elevation to feature's Z value (or something that indicates the 'z' value) of your objects. make sure you don't have a vertical exaggeration value and cartographic offset value .. highlight your object layer and select 'zoom to layer'. if still don't see turn off any polygon layers one at a time sometimes they will appear under the ground level elevation file / data . if still unable to see zoom out slowly and tilt / swiviel slightly to see if above ground elevation dem...if seen still high click info on elevation dem where point falls in 2d map window. make sure the pixel has a value and it changes correctly. If able to find objects in scene window please reply
