I can see both instances where both feet may/were off the ground in Leticia and Gethin's dance. Both seemed unintentional and tiny faults. I agree that Leticia's may have been her maneouvering herself into her last move and therefore she was not technically lifted by Darren.
From the judges point of view, I would expect them to heavily penalise a choreographic decision to break the rules.
On unintentional lifts, as as judge I would use my discretion: if I decided that it was unlikely that the celebrity could have completed the move without assistance, I would make an adjustment to my score.
If however, I made the decision that it was a minor error, I would make a substantially smaller adjustment.
An outsider would find it very hard to see the adjustment because I would be working within my mental quarter-point scoring. (for example: if the dance was nearer a 8 than a 7, but the unintentional lift may make me give a score of 7, but I could still give an 8).
As a judge (in a completely different sport), I expect people who come under me to accept my experience, knowledge and JUDGEment.