In the flashback, Stella is shown putting the handcuff on Owen's left wrist, and then he places the other end on her right wrist. She still has her bra on at this point. When they awaken, her bra is off and the right strap has not been cut. Once she was handcuffed, it would have been impossible for her to take off her bra without cutting the right strap. In fact she did not put the right strap back on until the handcuffs were removed, so it had not been cut.
When Owen and Stella arrive at the parking garage, there are vehicles beside Owen's truck. Even though they are only there a few minutes, by the time they go back to the truck no other vehicles are parked around it.
The amount of snow on the blue sedan goes from it being covered in the parking lot to none being present as it approaches a stop sign to there being some the roof and trunk when they pull into the driveway at the house.
After finally being released by Owen from the handcuff on her right wrist, Stella is shown putting on her jacket, wherein revealing her right shoulder and the return of her previously cut right bra strap.
When she reaches for her phone, there is a large gap in the handcuff on Stella's arm. In fact it is up to almost her elbow. If it were that loose, she could easily slip her hand out of it.
While one allows for some creative license in a LM, there is no way in any plausible scenario, hotels would give out guest information or let a stranger into a hotel room unless there were a warrant or police involvement, neither would a stranger on the phone get info on taxi or Uber or Lyft passenger destination information.