Is your guitar active or passive pickups?
The Alesis is only designed to handle line level inputs and outputs. Usually a guitar with an active preamp can interface line level inputs, but if it’s passive it needs a Hi-Z instrument preamp input. So you have to have an instrument preamp ahead of the guitar.
Alternatively, why don’t you Plug the guitar into a 244 input, remove the SEND/RCV jumper, connect the SEND jack on the 244 to the input of the Alesis, and connect the output of the Alesis to the RCV jack on the 244? This will use the preamp in the 244 to level-match your guitar (the preamps on the 244 are versatile and can handle instrument, mic and line level signals)…and then the preamplified signal, now at line level, goes out to and comes back from the Alesis via the SEND/RCV loop; essentially the same thing you are trying to do, only using the 244 as designed/intended.