Christ is "seated at the right hand of the Father" in glory.
Christ is everywhere in the Universe. ("In Him we live, and move, and have our being." Acts 17:28)
Christ is present among believers. (For where two or three are gathered together in my name, there am I in the midst of them Matthew 18:20.)
Christ is present in the Eucharist. ("I am that bread of life." John 6:48)
Christ is God. He can be present everywhere, in whatever manner He wants to be, because He is not bound by the limits of time and space. ("And all the inhabitants of the earth are reputed as nothing; and he doeth according to his will in the army of heaven, and among the inhabitants of the earth; and none can stay his hand, or say unto him, What doest thou?" Daniel 4:35)
And that is clearly incorrect.
Christ's onetime sacrifice for His sheep accomplished everything God intended it to accomplish -- to redeem the elect so that they would stand acquitted and blameless before God by the death and resurrection of Jesus Christ who paid the penalty for every single one of their sins, once for all time.
We are specifically told not to crucify Him again...
"If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put him to an open shame." -- Hebrews 6:6
To rebuke transubstantiation is to cut out the middle man...as God wills.