I checked the Computer Cache this morning. There are no trackables, so I've marked two of them as Missing that were still shown in the inventory.
Unfortunately not all cachers are careful to log these into their possession, and not all are diligent to get them moved to new caches. Gram and I have pretty much given up on releasing TBs and coins, they just disappear way too fast, and seldom reappear.
So sorry, we very much understand the disappointment of losing travelers. Hopefully these two will surface in a cache somewhere soon.