[Richard]

I am not known for tact, so please forgive me.
con
Was the coach working properly relative to leveling before you changed the HCVs?

I was taught to look for "what changed". If you wade through the posts, you changed the HCVs, then concluded they were in upside down. Then reversed them. Then you reported the driver tag won't inflate.
So it's important to know if the system was operating properly before the change. If it was, then let's go back on do some diagnostics on the HCV install.

I am confused about what you are observing. Is the problem the driver side rear will not raise? Is the problem the driver side tag will not inflate? Both?

If you look at the arm on the HCV, is it level? or pointed upward which would tell the HCV to put air in the bags?

We are trying to help, but we are limited on the full story, and you aren't answering questions about the situation that are asked. Sorry for my blunt comments, we are really really trying to help you.