It's quite possible the local dns to link where the images go is borked in the modem because of a weak wifi connection.
Try rebooting the modem to clear it, and it might just fix the problem.
Good morning Curt,
Thank you for letting me know, I've sent your account information to engineering which is still investigating.
Your patience and understanding are much appreciated.
I appreciate your patience while our engineers investigated and apparently have already rolled out a fix to some portions of the network. So please check and confirm that the iMessage issue is resolved for you. If it's still not working, the fix is still in the process of making its way to you. No ETA on when the rollout will be completed.