Things LE likely knows that we don't:
- Location of bike when found
- Condition of bike when found
- SM cell phone records including last contact, last location ping, status on/off
- Possible video footage from SM house cameras
- Possible video footage from neighbors' home cameras
- Specifics on personal item found
With the information above I believe LE has a strong suspicion on what happened and who else was involved, if anyone.
While there remains hope, it sadly would seem like there are limited scenarios with a positive ending here.
MOO.