When you tried to cast, did you receive an error message?
What is the make and model of your modem/router? Did you check if the band steering is enabled or disabled?
If it's enabled, could you disable it?
We'd like to make a follow-up on your chrome casting concern. Are you still having trouble when using Chrome cast? Your current upload speed is good as Home Wireless broadband offers up to 2Mbps of upload.