I recently asked why AME crashes when it should export something via dynamiclink from premiere (Premiere crashes when trying to export with Media Encoder via Dynamic-Link). But I only got the recommendation not to export with a network as a source.
Now I tried it again - and behold - it worked partly, though all videos were stored on the network-drive. Partly - because the sequence was rendered at a whole but a video within the sequence coming from another destination on the networkdrive than the others was marked as "offline" in the final output (not in the timeline!). Besides the different destinations the sources also differed in codec and naming. So before I took the step to convert everything, to see if the codec was the reason I looked at different patterns in the naming of the files. What caught my I was that the source which was marked as "offline" had 4 zeros in its name. So I deleted the zeros and - boom - it worked!
Conclusion: After figuring out that AME runs more stable with networkdrives when it is set as "run as an administrator" the second step which could help to run a job is to rename some files with same digits following each other which may cause trouble (so far). Though maybe it wasn't because of the digits but just because of the fresh conformation of the file when it was newly connected in premiere because of the renaming in the explorer.
Hope this helps someone.