Unfortunately, you can't detach Lightning from the chain. Channel closures can happen in any non-custodial wallet (especially if you didn't use it for two years). Sweeping requires an on-chain transaction (that was the morning you saw). You will be able to redeem the funds once the mempool settles down.  

 Thanks Roy. And as for the future, fees would be higher only, with ordinals in play. 
Have considered this dust.
As said lesson learnt. Would advice others with my experience:) good day.