First off, the damages claim of 20M is entirely nuts. Based on the substance above, she was averaging ~$375000 in annual billing or thereabouts....
So 20M would be asking for 50 years worth of billings. In a word, 'No'.
She is certainly correct, however, that Councillors who have a conflict of interest in a matter are supposed to declare said conflict, and generally refrain from voting on a matter.
Where a move is made to amend a procedure of Council, specifically in order to facilitate firing someone; if you happen to be under investigation at the time, you could certainly would be in conflict and ought not to be voting.
It is high as a billable rate for a lawyer, but not way high, rates on Bay Street for commercial law range from $300-$700 per billable hour. ( edit to add, I think the typical billing rates are excessive)
There is certainly a compelling case to be made for go for a flat-fee model instead. Based on her as-billed numbers above, it appears she averaged about 13 billable hours per week, give or take a couple.
The danger for both a lawyer and the municipality in flat-fee scenario is that the work load is undetermined when the contract is signed.
* an interesting question in my mind is whether the job of 'integrity commissioner' inherently requires one to be a lawyer.