PF jar ingredients, once sterilized properly, are completely sterilized inside the sealed jar.
PF jar ingredients, once sterilized properly, are completely sterilized inside the sealed jar. So you do not want to introduce any possible contaminants to the jar from the outside -in.
The PF-tek provides for inoculation using a spore syringe guided through the pre-stamped holes in the lid and directly into the substrate. Since you would not want to open a PF-tek jar (and risk airborne contaminates), this is the most foolproof way to inoculate PF jars. Now, if you had a sterile environment, such as a glove box or flow hood, you could simply open the sealed jar and inoculate with a spore syringe directly onto the substrate. But, there would be no point in this - as inoculation of the substrate is achieved by using a spore syringe.
You should not attempt to scrape a print directly onto PF-tek substrates. First, the spores may not rehydrate themselves adequately using the moisture content in the substrate, and hinder colonization. Second, opening the lid of the jar defeats the purpose of the PF-tek - to create a completely sterile environment within the glass jar. Opening a jar in a glove box or a flow hood would also render pointless, as you should have a vermiculite seal to ward off contaminates - spreading spores on the dry vermiculite layer will produce nothing (vermiculite is non nutritive and should have very little water in it - eliminating the requirements for colonization).