Some bacteria are pretty tough, so you may be lucky (but may be not). I have seen pretty well preserved biofilm on teeth, which were just dehydrated ("ethanol step", the easiest one). Besides dehydrating washing in graded solutions of ethanol helps to remove soluble proteins and salts, which, when dried, may form thick layer and cover bacteria.

I concur with Vladimir Dusevich's answer. You might have success looking at the bacteria without prior fixation and dehydration, or ... you might not : you have to try and see what happens with your specific sample.

I managed to look at E.Coli and Epidermidis on papers, without having to resort to a biological procedure prior to observation. The bacteria were however damaged by the vacuum and it was marginally better when working in low-vacuum mode without metallization.

I then suggest you work under low-vac conditions, if available to you.

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ESEM (environmental scanning electron microscope) may be the best decision, or you can use low vacuum mode of your SEM even without wet camera if you work fast, or cryoSEM