If I have part of the DNA, of a tyrannosaur and complete it with the DNA found from another tyrannosaur, can we be able to clone it on the mother cells of a Crocodile?
Also, Craig Venter can just synthesize whatever is missing in the first TRex. But might be cool also to use a giant turtle as recipient. The armor is maternally inherited via the mitochondria, so you TRex will have it as well.
In the real life, Craig venter was a pioneer in this field (http://science.sciencemag.org/content/351/6280/aad6253) but he did the thing with a small prokaryote (Mycoplasma mycoides).
For higher organism, just to try, you should transfer a whole nucleus with the right number of chromosomes (and this is really more complex than a synthesizing the DNA of an artificial genome). The artificial nucleus should involve: rewinding the DNA in chromosomes with their histones, selecting a single pair of alleles for each chromosome to generate the correct caryotype (no one more, no one less), confining the chromosomes in a nuclear membrane including all the nuclear enzymes and transcription factors. All this is needed just to make an experiment. It can even turn out that T.rex and crocodile eggs are not compatible for a correct development. You have a lot of work to do, but... good luck!
At present, the discussion is merely hypothetical. But, even somatic cloning of mammalians was considered bogus by most scientists, before Wilmut demonstrated it was feasible. I would be cautious to say something is impossible. There are still many problem to solve before being able to clone a dino, but we cannot definitely say it's impossible...