The skill on L6 tumbling is pretty high; anything under a C-value is permitted. In concrete terms, this means that going backwards she can do anything up to a 1/1, and forwards she can do anything up to FLO 1/2. Connections don't increase the value of a skill, so any allowable skills can be done in connection.
So for example, if a gymnast really wanted to push the difficulty limits, she could do FLO 1/2-whip-BLO 1/1 for one pass and FLO-FLO for a second pass, and she'd still be fine for L6.