I don't have issues with this fight.... Especially with Phase 2. I use Marron > Synchro > Rappy rotations. Killing the nodes is easy with Rappy Stomp, Generic Synchro Combo, and I've had lv3 Marron 1-shot PD's parts.
If anything, Summoner have it easier with Dia Master, I never have to worry about my HP. I only top off to trigger bonus dmg from Perfectionist (R).
Are your pets at least 13* and have sweets in their box? I would like to share more insight on how to make this fight easier... I'm usually one of the first few done in my alliance for solo PD.