Pressure canning stock I used egg whites to clarify chicken stock. I filtered the stock through cheese cloth and fine mesh colander two times.

After I pressure canned them I noticed that there was egg white on the bottom of the jars. Is this still safe to keep or should I open, restrain and then pressure can again?
In any food safety situation you really must ultimately ask yourself 3 questions to determine relative safety:

How High of a temperature am I sure I achieved?

How long did I hold this temperature?

How well sealed is the container?

If you are pressure canning, there are reasonably good chances you kept VERY high pressure and temperature. As for time, I cannot say.

For years my grandparents, my parents and myself have canned vegetables, soups, stocks, etc. and only rarely did we have errors because of some content of food. Most of our spoilage came from broken seals.

If you're confident in your canning technique, I see no reason why some egg white would hurt your stock. It's an animal protein just like any other.