[IJF1]

The Flink's videos 'Drive, Focus and Grip' and 'Preparing your dog for the helper' give good advice on playing tug with your dog and getting a good grip foundation on your dog at home. Hopefully your trainer will not just evaluate your dog but give you advice on the best way to develop your dog's drive and grip.

As for getting a Rott to bark, this can be a bit of a challenge. IME frustration (teasing with a favourite toy) will eventually get you a bark. As soon as you get one bark BIG REWARD. You can then work on this over time to get more barks and even put it on cue ('speak' command).