Problem opening TIFF file in Photoshop CS6

HI.

I have a designer who is having a problem opening a tiff file that she says she edited previously.

It's a large 2.7GB file 18620 x 10962 px.

From her words, originaly it was an EPS that she opened and did some work and then saved or exported (I don't know), and when she came back to it and tried to open in Photoshop she couldn't because of an error about Photoshop version incompatibility.

I've uploaded the file in question to my google drive if someone would want to look at it.

Here is a link to the file zal.tif - Google Drive

Any ideas why that could happen?

If any additional info needed please ask.

Thanks.

Pavel.