In most cases, yes.
In regards to most banes or boons, this is correct; these two feats can cancel each other out but there is an important distinction, notable in the timeframes by which the invocation is sped up by Boon Focus II and slowed down by Heightened Invocation:
Boon Focus II
[...] you may invoke the boon one time increment faster, as follows: If the invocation time is a major action or move action, it becomes a minor action. If the invocation time is 1 focus action, it becomes 1 major action. If the invocation time is 1 minute, it becomes 1 focus action. If the invocation time is 10 minutes, it becomes 1 minute. If the invocation time is 1 hour, it becomes 10 minutes. If the invocation time is 8 hours, it becomes 1 hour. If the invocation time for a boon is 1 minor action, it can be invoked only once as a minor action. Beyond that it can be invoked by expending a move or major action.
Heightened Invocation
When invoking a bane or boon, you may choose to do so as a heightened invocation. The invocation time for a heightened invocation is one increment higher than usual as follows:
- 1 action becomes 1 minute
- 1 minute becomes 10 minutes
- 10 minutes becomes 1 hour
- 1 hour becomes 8 hours
- 8 hours becomes 24 hours
As indicated by the parts bolded for emphasis, Boon Focus II can, at maximum, decrease invocation time for banes or boons from 8 to 1 hour; 8 hours is the regular longest invocation time. Due to Heightened Invocation potentially causing something to take 24 hours to cast, Boon Focus II cannot work against Heightened Invocation when it is used in these cases.