Is there any way to import the KeepKey wallet to either the Jade or the Coldcard using the backup seed?
At the risk of stating the obvious, if you just replace the word "import" in your question with "restore", you've got your answer.
I.e. you restore your KeepKey wallet to another wallet (be it Jade or Coldcard) by entering your backup seed into the new wallet. No transaction occurs onchain.