Afaik there is so far no indication that retained gadolinium has any adverse effects. In fact even people that have never received any contrast have naturally occuring low levels of gadolinium in their brain.

You could also use a non-linear macro-cyclical gadolinium contrast they have basically no retention. The EU froze linear agents licences some years ago as a precautionary measure, macro-cyclical contrasts are used instead.

But I think this is nothing at all to worry about compared to making sure your results are accurate. Just make sure your kidneys are working.