Was I right?

[Ed Maeder]

The other umpire was correct. Third base and home are both the plate umpires calls. If there was a play at third, (sounds like there was) the plate umpire should have gotten inside for a call at third. When the overthrow occurred your partner should have stayed inside and gone home for the call. rwest is also correct in that if you deviate from prescribed mechanics you communicate. If the play was covered well and you communicated this change could work.