Jag,
Considering the time now I'd expect this message come a little late.
I think you ought to be making decisions right now.
1 . You'll have the garage the car is at now fix the issue, no matter what.
2. You'll transport the car without any further dismantling to a known A2 savy workshop for diagnosis
3. You'll cut your losses and offer the car for sale as a project.
I make the above based on what you've said about the garage the car is currently at.
If it's the chain and tensioner, which seems likely, the workshop haven't realised yet that to remove the sump they will need to remove the gearbox (beacuse there are hidden bolts that cannot be access if the engine will not turn).
This means there is a lot of effort, and I'm sure a fair bit of expense for you, in the dismantling of the car.
If the choice is that it's not going to be repaired by the garage it's at, not many workshops will take on the work, as they won't know the condition of what's been removed and may not want to warranty any repair.
If you decide not to repair the car and offer it as a project, then it also becomes a nightmare for whomever buys it - and certainly it will be worth much less in pieces.
You shouldn't feel disheartened though - but you should have some clear thoughts in your mind about the immediate next steps.
Cheers
Jeff