The project has been delayed in the past.
They did not wait for another bidding round.
Since "they did not wait" is in the past, "would delay/would have delayed" has to be in the past (or present perfect) - "would have delayed"
If the sentence said "We can ill afford to wait ..." it would be appropriate to use "would delay".
Besides, we don't know if the project is still delayed, only that it was delayed at the time of not waiting for another bidding round. If it is no longer delayed, then saying that something "would delay it further" doesn't make sense.
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