Grammar

Hello. I have a question. In the following paragraph, are the words 'bent' and 'if' instead of 'bending' and 'whether' correct grammatically? I know the paragraph is somewhat long, but I wonder if the words 'bending' and 'if' are possible without the change of the original meaning

Picture for a moment the familiar scene of a NASA mission control during any shuttle launch or space-probe landing. It’s a room filled with individuals, each [bending/bent] over in front of a computer screen, working in concert to achieve what no single one of them could do alone. Each person, each link in the chain, has a small but central role to play, and each relies on the trustworthiness of the others to do their jobs. If a single individual fails to notice an important data point — [whether/if] it involves the pressure in a tank or atmospheric conditions or the heart rate of an astronaut — the whole enterprise can be in danger. Everyone has to trust the others to do their jobs and do them well if the joint venture is to succeed.

Please answer my questions. I always appreciate your kind reply. Have a nice day!