TSA (or the foreign equivalent) is not required to leave a love note. The fact that you are using locks that they can not open means they are going to cut them off. Consider yourself lucky many years before all the TSA approved locks TSA tried and failed to cut a lock off my bag. So they cut the zipper pulls in such a way that I had replace the zipper. TSA denied my claim because they said they have the right to inspect my bag regardless of the fact that they did not have the proper tools and would break int o my bag if necessary.

That said, when did you notice the locks missing?? In SEA or PDX? If SEA then they were removed in AMS, if in PDX then they were removed in SEA.

Finally as question, you locked your bags, what did you expect TSA to do? Page you and have you come open the locks for them???