Preliminary construction contract signed - Additional costs without a construction crane?

I am curious whether the crane can be set up. Maybe everything will work out as planned, then these thoughts would be completely unnecessary. Thank you for the answers.

I have to say, I really can't interpret that clearly

.. and I wouldn’t put it as generally as does now. After all, it is a preliminary agreement .. read through all the clauses about it.

The contract hasn’t even been concluded yet. The general contractor realized at the last minute that he might have problems with the crane there and is now checking whether that is true. If so, he will revise his offer.

It came as a letter from the construction company...

... thank you very much for signing the preliminary contract. Unfortunately, we cannot yet countersign the preliminary contract and therefore cannot yet guarantee acceptance,...

The issue with the crane arises, that in a similar case it cost about €8,000 extra, building without a crane, and that shell construction companies have been contacted to take a look on site.

What makes me a bit suspicious, however, is what is stated in the presentation.

If the preliminary contract between the client and the contractor for the construction project at a total price does not come about for reasons not attributable to the contractor, a flat rate of 5% of the fixed price is agreed as reimbursement for the construction submission documents. If the contract for the execution of the entire construction project by the contractor comes about, the costs for the construction submission planning are included in the fixed price and scope of services.