It's in the mod list, as I mentioned, further down. It's one of the mods that display a team HP pool, but also has other sub-options.
There's no hot key. They display when you aim at enemy tanks.
Probably shouldn't check both options, but rather just one. If PMOD isn't working for you, uncheck that, and check the Battle Observer one. See which one works - otherwise - we're back at the "Please attach log files" part