The episode starts off in new footage.
Here's new footage of Batlings, Jinxer, Vypra and Loki
This shot of the 5 Rangers is when it goes to Sentai footage.
The shot of the fire that came from the Cocoon that hits Vypra, Jinxer, Loki and Batlings is new footage but it hitting the Rangers is Sentai footage. After you see the fire hit Vypra, Jinxer, Loki and Batlings, as soon as it changes to the next scene, it's back to Sentai footage.
This shot of the 4 Rangers is when it goes back to new footage.
Once you see this shot of the Red Ranger then it goes back to Sentai footage.
All footage of Vypra, Jinxer and Loki in Mariner Bay is new footage unless otherwise stated.
This shot of the 5 Rangers is when it goes back to new footage.
Here's new footage of the Red Ranger charging towards Olympius while the other 4 Rangers are still down
Here's another shot of Olympius, tthis time firing a beam at the Pink Ranger which captures her
This shot of Jinxer is when it goes back to Sentai footage.
This shot of Batlings, Vypra and Loki is when it goes back to new footage but based on previous info, you already knew that anyway.
All following shots of the Red Ranger until the Skull Cavern scene is new footage. With the Skull Cavern scene, I'm unsure about some of the Jinxer/Olympius stuff within the Skull Cavern but I'm pretty sure that everything else is in new footage.
Here's new footage of Thunderclaw and Jinxer in the Skull Cavern  
Here's a shot of the Aquabase's interior This appears to be in the Weapons Lab and here's a close-up shot of some Aquabase controls
Here's more new footage of Olympius
Here's new footage of Thunderclaw
These shots     are Sentai footage which means it's back to Sentai.
This Thunderclaw shot means that it's back to new footage.
This shot means that it's back to Sentai footage.
These shots   are new footage so this means that it's back to new footage.
This shot means that it's back to Sentai footage.
These shots   are back to new footage.
These shots of Thunderclaw   are Sentai footage which means that it's back to Sentai footage.
The footage of Jinxer appearing in Mariner Bay in order to throw his Growth Card in order to revive and enlarge Thunderclaw is Sentai footage.
All Giant footage is Sentai footage.
The last Skull Cavern scene involving Olympius, Loki and Vypra all appears to be in new footage.

Following info comes from GoGoV Episode 26.
Here's Thunderclaw  
Here's Olympius  
Here's Giant Thunderclaw