Opening Channel transaction with pushed sats not in mempool. Help?

Try this, just to check before doing other crazy things.
Import the seed in Bluewallet or Sparrow or Zap (desktop). Just to see if the tx or funds are back to your onchain.
Follow the instructions from this guide if you want to use Sparrow.
If the funds are back, then you could start the process of re-scan utxos in your umbrel.