I wouldn't say that puts the rumour to rest. "Nothing has been decided" certainly implies it's possible that the ride could be closed next year so they can refurb it.
I haven't listened to the video so apologises if what I'm say is just a repeat of what was said in that, but from what I've been told:
-Valhalla costs over £1m a year to operate
-The park need to spend approx. £900k to simply fix it up and make it ready to operate again
-On top of that, the park want to spend extra money to improve the longevity of the ride (in the 20 odd years since it's opened, technology has improved, etc etc)
So the logic is if the park close it for a year, they immediately save enough to do all the fix ups it needs. They can then have extra funds to, as Amanda puts it, make it more sustainable, and do it as one big project.
For a ride like Valhalla, to hear the park want to make it more "sustainable" should ring alarm bells. That immediately sounds like they want to cut costs so it's less expensive to run. Of course, the key cost down to the water - pumping it around and making sure it's clean, so they can't cut that, but other things can be pulled I'm sure. Hopefully that's not the case and they're just planning on improve the hardware of the ride.