I think support is incorrect; afaik the only Bitcoin sportsbook that uses the "true" live asian handicap markets are BetBTC and sportsbet.io. Everyone just has them as a normal handicap. I would probably complain to support for misleading you causing you to make a bet that you wouldn't have otherwise made and ask them to pay the bet.

It doesn't seem like Bitsler has sports rules listed anywhere (or I can't find them anyway) so I think this would fully be the fault of support.