Deck Spot Elevations

Good Afternoon!  I have a unique bridge project I am working on where we are putting a park on top of our bridge.  I am looking to see if there is an easy way to determine the top of deck elevation from the bridge model and various spots.  Prior to porting my model over to OBM I had my bridge model created in ORD using corridors.  This was nice because when I wanted to check the deck elevations with respect to the landscaping spot elevations given to determine soil depths, I could use the Civil Analysis --> Analyze Point tool, select the deck element in the corridor, and the tool would give me the deck elevation when i snapped to the 2D spot elevation location.  This civil analysis tool does not work with the OBM bridge elements and I don't see any sort of similar OBM analysis tool available.  I kind of thought having a tracking tool like this in OBM would have been a no brainer, but it appears I am wrong.  I am currently debating extracting the top of deck surface from the deck solid and then trying to create a terrain from that, but im not sure how good the DTM will be giving it will be trying to create it from a B-spline curve surface.  Is there any simpler way this can be done?  I have a lot of spot elevations to check and i will most likely have to check several grading iterations in the future.  Any help/suggestions would be very much appreciated.  Thank you!