There were many points in the manga where it seemed like Nobunaga was making stupid decision after stupid decision just to get bailed out by Jesus (Ken) and his other retainers but that's been happening more and more lately. Him being cryptic for no apparent reason like with what happened with that Badger gift means any misunderstanding of that sort that doesn't get solved could turn into a disaster. I don't know if that's intentional or not by the author. Maybe if he wrote Nobunaga as being better at diplomacy then there would be no room for Ken to showoff?
Also there's a weird dichotomy where the more he relies on Ken the more he's willing to risk Ken's life for little gain like a cheap disposable pawn. It's like risk management is a foreign concept to Nobunaga?
It's been a while since I've reread this manga, but this event is probably intentional. In short, the podcast about Battle of Nagashino I've listened to talked about the need of secrecy to achieve victory.
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Longer version:
Chapter 118, page 14-15 show that since Katsuyori is capable, they need to bait him out.
I'm not sure how accurate the podcast I've watched is (it did give some sources, so it's probably has some right), but it mentioned that the relationship between the Oda and Tokugawa is pretty bad during this time.
The Tokugawa has proven themselves a faithful ally for the Oda that help them nonstop, but as mentioned in ch. 117, the Oda didn't do the same during the Takeda's attack. The podcast mentioned that it gotten so bad that the Tokugawa goes "Either help us or I'll switch side and conquer your home province for myself."
There are some more details, but the manga might show it so it could be spoiler so I won't mention it.
The podcast I'm referring to is this:
https://samuraipodcast.com/ep39-the-narrative-and-analysis-of-the-battle-of-nagashino