Can recruit tokens go back into your hand?

Yes, Recruit tokens can be returned to your hand.

According to RiftJudge FAQ #4395, when a Recruit unit token is returned to your hand (for example, by a card effect like "Gust"), it is moved to your hand and then immediately ceases to exist because tokens cannot exist in any non-board zone.

Additionally, Rule 180.1 confirms this mechanic: "If a token is put into any Non-Board Zone, it ceases to exist immediately after moving to its new zone."

Because the token ceases to exist upon entering your hand, it does not count as "dying," and it will not trigger any "when unit dies" abilities.