You already cited my 2008 tests with other than TLM 103 capsules in that mic, so you already know that foreign objects will probably not improve your situation, let alone, match the sound of your other, intact, TLM103.
I see two practical solutions:
1. Buy a good, used TLM103. Completed eBay auctions for a TLM103 set, including wooden case and elastic suspension mount, average in the low to mid $500s.
2. From what you write, there may be some remnant moisture or contaminant left inside the capsule, which may not have been sufficiently removed in the two previous cleaning efforts (most people use simple mechanical cleaning-via brush-which is unsuitable to remove heavy contaminants completely. A truly professional cleaning, together with preventative maintenance by the user (pop screen, plastic bag, etc.) may be the cheapest solution after all. If Neumann, Berlin could take a look at the capsule, that would be the cleanest (so to speak) option, though it may take some time and customs/import efforts.