‘Taxpayers and tenants have a right to know how much they spend, from repairs, to rents and expenses.'
No they don't - this is the Landlord's concern. If the Government thinks HAs aren't spending appropriately, it should stop subsidising them.
Taxpayers hold the Government to account for how the Government spends our money. It is the Government's responsibility to spend our money appropriately - clearly it hasn't put in place safeguards and thinks the money it has assigned to HAs has been misspent. If HAs have actually breached contract then the Government should take action against them - otherwise this sounds rather like an admission of failure by the Government.
One that some of us have reckonised long ago.