Only if they don't promote their arm from what I've seen. They basically have to bounce over, he clearly moves his arm forward after it hits the ground.I have seen tries like this allowed due to the fact momentum carried him to the line anyway.
Promotion of the ball is inherently suggesting two separate movements. I.e. 1st movement ball touches the ground, 2nd movement ball promoted to the try line
If the ball touched the ground and then he pushed it forward for the try then no try... but the ball only touches the grass because he's in the process of promoting the ball