Forcing Shyvana into the jungle won't fix her
Let's face it Shyvana will never be a better on hit champion than Warwick unless you completely destroy one of their kits. She also will never be a better on hit champion than Udyr. They both have things she does not, like attack speed bonuses in their kit, and hard cc.
Forcing shyv into the jungle only based on clear times will not work. Because you are going to balance on hit items around warwick, when he is better at them than her and has way more solid ganks than her. Warwick with the same items will beat shyv. Udyr with the same items will beat shyv. You are balancing her against stronger champions for what you're forcing her to do. Shyvana isn't an attack speed based on hit champion. She is a mixmatch patch of strengths and mostly a ball of stats.
Her presence top was the best period and place for her. She makes an excellent top. As a jungler, her teammates despise her. Utterly hate her. Wish she wasn't on their team. Why is that Riot? maybe because she doesn't sit well or perform well in the jungle. Because she is not a good jungler. Clear times don't make a good jungler. Having good clear times isn't the essential thing you need to jungle and that has been proven over and over and over. Ganks are. Counterjungling is niche but is a form of ganking. Shyvana gets outshone in both of these areas as well.
Shyvana only brings damage and later tankiness. She is one of the most hurt by league of mobility. Her kit cannot withstand the era of Kallista. She had safety and stats top to be a bully, and an ult if used well could help teamfight. She can split push and duel but has trouble securing any kills. You nerfed her numbers and she has never recovered. Bandaiding her with a 20% more damage on one spell in the jungle isn't going to do anything for her of note. She will still lose to every gank jungler in the game in higher ranked play. Because getting kills and getting your team ahead will always be a better strategy than one person on your team having a bit of stats advantage that are only relevant if the gank jungler fails every single gank they attempt. And that is never the strategic point you wish to gamble on. "I'm going to afk farm the jungle and hope Lee Sin fails all his ganks, if he does I win" is a terrible terrible direction to take Shyvana. Can she counter jungle? Sure anyone can. She isn't good at compared to many other choices though. Can she counter gank? Sure but what is the point if league of mobility leaves them the power to choose whether to fight shyvana or not? Lee sin and j4 will hop away and shyv only prevented the inevitable as next time she is not near the lane or back or too low hp or a million other factors. So she isn't a good counter ganker unless the other team is dumb and throws themself at your feet. Can she jungle clear? Sure, so can lots of people. And they can gank too. And those ganks get not only them ahead, but objective control and their lane ahead. So she isn't a good jungler b/c she has a losing strategy. Her stats were all she had, that's why she went top lane. Now she can't win even there.
It's not impossible to win with Shyvana. But looking at win rates, it looks to me in higher level ranked play you have a much much better chance at winning with urgot than shyvana and it's been that way for over half the season. The only person that competes with her pure shittyness at the moment is Yasuo.