I believe so, all the balance I had was onchain and I managed to get it all out but the 25k sats
In RTL there are no channels in the "open" tab, and all channels on the pending/inactive have a state of "onchain"
Discussion
How many blocks have passed since channel close transaction?
94 confirmations (might vary slightly for each channel but not by much...)
Cooperative close?
I'd say so, all the funds were available onchain afterwards.
I chose to send out all available balance, and the node made a transaction with all the utxos with 2 outputs + change, one to the address I chose and another one with 25k sats to an address controlled by the lightning node.
Update: tried again today and the transaction went through.
Even though the channels were showing as closed in RTL and the transactions were confirmed onchain, in core lightning GUI it showed I had 3 channels still open, today the core lightning GUI no longer showed any open channels and the transaction went through.
Probably had to wait for some timelock