Tom B is a great fellow, a marvelous Festool dealer and has never steered me wrong.
When Tom says Leitz is Festool's contract manufacturer of their circular saw blades, I am absolutely sure he is correct.
When I purchase Festool brand blades I could care less in which factory they are made, because I have faith they are made to exacting Festool specifications and are inspected by Festool technicians.
It well could be that Leitz has a sharpening facility close to you. They have an excellent reputation.
Mind you, to effectively sharpen Festool blades for the Kapex, TS55 and TS75 the shop needs modern equipment. But the same can be said for most top-quality blades, bits, drills and machine knives.
Once I tried an experiment, just to be sure LA Grinding was doing a marvelous job. I sent a TS55 Fine Tooth blade to another grinding service with a good reputation and within a half-hour drive. That was the second re-sharpening of the blade. After waiting 5 working days for a call saying my blade was ready, and hearing nothing, I phoned that other firm. They said they needed a few more days and would call me when it was ready for pick-up. A week later they did call. The price was slightly higher than I was paying LA Grinding, but there I am a high-volume customer. I expected to pay more the first time I tried a different service. Unfortunately after taking so long, that other service had damaged my blade. Trust me, I have blades re-sharpened before most folks would consider they need it. That blade fresh from re-sharpening cut far worse than when I took it in. I explained to LA Grinding about the experiment. For just the price of a normal re-sharpening they repaired the damaged blade.
Compared to the far larger blades I use on my slider table saw and the somewhat larger blades I use on my beam saw, re-sharpening the TS55 blades is far less expensive. The purchase price of the TS55 blades is also less. But, I still need excellent blades to make excellent cuts.