Having trouble with ETA Stage Defense

This week's stage defense doesn't seem difficult at first glance, but Temple is randomly getting chunked by 30-50k damage and just dies before I make it to the basement.

I wasn't sure if it was the Efervon balloons or the Efervon environmental damage or the void fissures or just attacks from enemies, it's a bit hard to tell with all the stuff going on screen. In the previous weeks it was no problem with Ancient Healer but with gear embargo I can't summon it.

Any generic advice that might help? I'm running it in a duo with a friend. We could do the alternating carry in 2 full runs if we have to but I prefer not to. I have Khora, Titania and Ember for frames.

Thanks.

edit:

I'm trying a few things that seem to help, although I haven't yet passed it solo. Waiting to duo it with my friend which should make it easier.

• Well of Life: according to wiki, this heals defense objects without the usual limit
• Null star with augment: cheap ability that provides damage reduction and homing aoe projectiles that guarantee a heat proc to stun enemies
• Duplex bond on sentinel: 3x invulnerable sentinels to distract enmies and 3x verglas primes to kill enemies
• Roar with augment: 5 puncture procs on all enemies in range to reduce their damage by to 80%
• summons seem to distract enemies well. Last week I had nekros which felt a lot easier than this week when I don't have a lot of summons. An alternative would be subsumed summon abilities like molt, decoy, mind control, resonator.
• radiation: more soft CC

edit 2:

did it with Null star Titania and Sevagoth team mate. Titania's mobility was great for balooons and Sevagoth's gloom and nuke for everything else.