If Tuk is hurt and unable to skate to the best of her abilities I think it's smarter for her not to compete at COR honestly. She'd have to win to make the GPF and Adelina and Anna have both already qualified and Julia is likely to join them. A sub-par competition for Tuk could lower her stock heading into RN and I don't think that's something she can really afford with Julia skating so well this season and Anna rising up the ranks. If she doesn't compete, she doesn't have a chance to make (or miss) the GPF and she can go into Russian Nationals with less pressure. Based on scores this season, she doesn't really have a PCS cushion to Julia or even Anna, and given how consistent those two have been thus far, she really needs to focus on Nationals (and likely Euros) and bring her A game there if she hopes to get to the Olympics. GPF could be a distraction, if she doesn't skate well at COR it could be a red flag and Pogo could overtake her in terms of pecking order for the Olympic spots, and if she's hurt then that could throw a wrench in everything.
The smartest thing would be to withdraw, recover, then focus on training for Nationals and doing well there. If she goes a little under the radar between now and then, she might feel less pressure and skate better.