I am facing an Issue in Odoo 15

One of our clients was previously engaged with other Odoo Partner who have Imported Beginning Inventory in such a manner that the Inventory showing in Quant has no effect in Stock Moves, Product Moves and Account Moves

Now there Balance in Hand not matching with any of the report like Stock Valuation, Product Moves and Inventory Valuation ledger , they posted a Journal Entry for Opening Stock Value Separately to show client their Matching Trial

If anyone of you have face similar issue and how this has been resolved by them. Or any idea can be welcome.