Getting all the Fynni pets required is pretty easy seeing as how you can get a free blossoming cage for each of your alts in a few minutes of work and use them to blossom werewolf gems. Even at rank F you'd get a level 150 pet for basically no work.
The real challenge is the 500+ magic powders. It took me an hour straight of hitting a lamp post to get enough gems to make around 30 even with the trade in quests. Maybe I'm just unlucky.
It can sound kind of wasteful, but you can "enchant burn" anything, even a single piece of gold, and you'll "fail" and receive 1 Magic Powder in return.
It's basically using a campfire to turn Any Item + 1 Holy Water + 1 Mana Herb into 1 Magic Powder.
Also about hitting stuff for gems, have you checked out the shop area sign over in Port Cobh?
It's over by the area where you can set up personal shops, and has a higher-than-normal drop rate compared to almost every other normal whackable object.
Wow with only 3 Rebirths, that's gotta be almost 50 level 200 sacrifices!
Was that also enough to get your doggo up to r1 Fynni Mastery and r1 Gao?