Thanks Guy Betsy.
Indeed Ethiopian ground staff has been much more helpful.
1. Their 1st answer was : "With regards to your query below, You can request SQ to interline your bag directly to ADD on ET601 at the check in counter. In the transit lounge at dubai you need to go to the transfer desk and contact the DNATA transfer desk staff who will pre-check you in and give you your boarding pass you also need to show them your claim tags to ensure the DETAILS are entered in the system and the bags are automatically transferred on ET flight. Please be informed that your bag allowance is 40kgs per pax and anything over and above that you will have to pay for the excess @ AED30 this is for the sector DXB/ADD"
2. Then upon my question "what if SQ does not agree to check through" they reverted with following answer:
With regards to the tagging of your bag you will have to check with SQ at Singapore about the procedure of tagging the bag as each airline has their own procedure. It you are holding a separate ticket dxb/add then they may tag your bge only to dxb and not to final destination in that case you will have to inform the transfer desk at dubai airport and show them your claim tags so that they can reroute your bags on ET flight.


So everything should be fine. I will update you guys if anything goes wrong!

Cheers