Routing asset PR's to cost center manager

[Currie, Kim]

We're on 4.5b using WF for PR approval.
 
The current set-up:
WF triggers and routes to the cost center manager based on the cost center
assigned to the classifications assigned to their release strategy using
account assignment "K".
For an asset PR account assignment "U" is assigned, and routes to one person
for approval because no cost center is assigned to the PR.  The asset number
is assigned to the PO after release.
The reason I'm told they set it up this way was they didn't want the
end-user to create or ask for the asset number at the time of PR creation.
 
Management now wants PR's created with account assignment "A", with the
asset number assigned so the appropriate approver (cctr. mgr.) approves.
 
We changed the classifications of the release strategy to include account
assignment "A" (removed it from the other strategy).
We create a PR with the account assignment "A", assign the asset number
which was created with the cost center, the PR is not subject to release.
 
You'd think it would just work adding the classification to the strategy.
The cost center assign to the asset isn't triggering the WF, maybe because
it's buried to deep in the PR?  We tried reconfiguring the PR so the cost
center displayed or was mandatory, but it wouldn't take.
 
 
Is there a fix that would allow PR's assigned to an asset to route based off
the cost center assigned in the classifications of the strategy?
 
'Appreciate hints or any help to steer us in the right direction.