After my visit here on 2018-07-11, I can witness that this TB really is not present in GCP5DA. Your TravelTag was discovered just 3 days after dropping here by geocacher horny_cb, who wrote here in Czech: "Noticed in hands of geocolleague gajda1". Gajda1 found the geocache on 2018-03-31. Be sure to ask gajda1 whether he still has it in any pocket, but did not logged it properly yet. There is a small chance, or he can say eventually, where it has gone. (Gajda1's profil: https://www.geocaching.com/p/default.aspx?guid=5dc06625-e0c8-4d48-bd6f-fc63bb97e7ce)
Unless your investigation is successful and because now the trackable can be wherever, but absolutely not here, I ask you, mustangok1, for marking it as "missing". Thank you in advance.