I respect your opinion and theory. I truly do. And I fully believe folks should be considered innocent until proven guilty. I would like to understand why you think this is what (may have) happened. Is your theory, then, that this individual has taken the life of Gannon (thus the daily searches to find his remains)? Or is your theory that this person is holding Gannon for some reason, and has planted/left evidence in the areas that have been searched to throw-off investigators?
IF your theory is accurate, (and we know without a doubt there are numerous surveillance cameras in the neighborhood), why wouldn't LE release photos, vehicle information, time of departure, description of potential poi/suspect to the public? What would be the purpose of withholding this information if they feel Gannon is endangered? I don't believe they would keep this information from the public in order to prevent "tipping off" said individual? It could potentially be a threat to the public's safety, IMO.
If TS knows who is responsible (addressed in her statement), why hasn't SHE, in the interest of bringing Gannon home, provided the information to the public? How can the public be on the lookout for individual(s), vehicle(s), etc.? LE has indicated that ANYONE with information about Gannon's disappearance is considered a POI. Wouldn't she want (even against LE's advice), to take the public's focus off of herself?
I, personally, do not believe LE would be utilizing the services of numerous entities, digging in the snow at numerous locations, and collecting forensic evidence from the home or garage numerous times if the investigation indicated Gannon left with/was abducted by an unnamed individual. (Of course this would be my theory regarding the evidence collection I mentioned. I would be left to speculate that said individual would not want to risk losing a hair, dropping skin cells, leaving a fingerprint, or any other trace of themself(s) inside of the garage/home. But what would be the purpose for the collection then if the individual met Gannon outside)?