There's a key point of how Yt works that you need to be aware of.
At 108 subs, your viewers will 100% be other channels through search (assuming they'll scroll a few pages to where you will likely rank), general browsing, and anyone coming in via s4s loops. When you run Adwords, Yt sends your videos to "real people", that is, viewers without channels. These generally will not sub to a new channel at low subs (which is why you are hiding your sub count I assume).
The only exception here is if you hit highly popular keywords with relatively low competition and pull a few rabbits out of the secret seo grey hat.
Back to the dilemma - running Adwords puts your videos in front of real viewers who don't care for small channels. (it's just a fact, nothing personal, exactly the same happened to us).
I think you're wasting money on Adwords at your sub level. Unless you have a budget of $3-$5k over the next 2-3 months (seriously) as that's what it will likely take to push through. I would recommend Adwords at least at 300 subs, better at 500, with a good backlog of videos, perhaps 30+, maybe even 50.
Best thing to do is focus on popular tags in the kids/toys area, make lots of fun, happy, emotional videos that get viewers excited (this will be other channels at this stage). Once the algorithm detects you're on trend, have good retention, it will auto-place you on suggested of 10-50k sub channels for a few test slots and see how you perform. If you perform well, it will place you on higher sub channels. That's when you get real traffic from real viewers and start to grow organically.
Another thing, is pick 10-20 channels you admire at the 2000-10000 sub level (don;t go higher, there are other factors at work at high sub levels), and carefully, very carefully, study their breakout videos, playlists, seo strategies, etc, to see how they broke out. Adopt similar strategies.
Cracking 1k subs is hard, 2k hard but easier, 5k even easier, so is 20k. It's so much easier to get from 10k to 20k, than it is from 100 to 1000. After that it's pretty much on auto-pilot as long as you keep the algorithm satisfied.
Thx for the info!