Hmm, it's already using 0.0.0.0 so in theory, it doesn't even need the other bind settings.
Can you try to set
rpcallowip=your_network_gateway/16 (
e.g.: 192.168.1.1/16) to cover all of your local network's IP addresses.
Are the machines running with static IP? If not or not sure, this should work.
Also, I'm assuming that those ":" are also typos, because those should be "=" or will not be parsed otherwise.
If nothing works:
AFAIK, Sparrow writes something to its log file if there an issue with its configured server connection,
Try to check the "
sparrow.log" file in you Sparrow Wallet's data directory.
In case you don't know its location, refer to this documentation:
sparrowwallet.com/docs/faq.html