Well just a little note. If like you said you were given permission to enter the Bravo airspace to conduct your work it is generally the ATC who is responsible to separate you from other a/c in the bravo or outside period. Hence, the fact that ATC can deny you entry in the Bravo (to busy to keep you safe). That is why you may hear at times when you are flying under VFR rules the phrase "you have left the ABC bravo airspace with some other interactions". This is to notify the pilot that you will no longer receive Class B separation. Now, overall I don't really have the full details but well from the picture you paint I don't see much that can happen. You have done exactly what a pilot should do in these cases. File a report with your side of the situation, ATC will do the same and somebody in some back office may review and deem non event or you may receive a call for more info or you may not hear anything at all.
I would not loose to much sleep over this.......and someone said this is a non punitive environment. Most of the info is made to be a learning tool for all. And overall in aviation, any type of incident has multiple layers.....not just the actions of one individual.
Hope this helps. If you get any other info or feedback that you need help with feel free update us all.