Rollinheavy

I have a 1998 audi a6 c5 2.8 quattro. It does not want to accelerate at all. The tcm was already replaced once. But it seems like it doesnt even want to shift. If the gas is fully depressed It sits at 1500 rpms and goes no faster than 10 mph. I cleaned the maf sensor. I'm thinking it might be another sensor or maybe a clogged cat. I'm not sure, thats why I need some audi experts to help me out. I also rented a scanner from autozone to scan it and it wouldn't. So I would like to know if there is a certain scanner I need to buy or a secret way to pull engine codes. (Tried the paper clip trick, few different ways, tried a volt meter, tried cycling the key, while hitting the trip meter. ) Idk I'm lost with it need help.

Thank you,
sean
here is a link to a video of what my audi is doing
https://youtu.be/v5EuCAmBq5Y