Remember having a friend in a similar situation. This was my advice in that moment:

-Make a list of the top 50 clients you had in the consulting firm, choose those which you had a close relationship and can actually talk about you (not fake it)

-Call them and ask them if they believe you did a good job and if they were satisfied with your services. If the answer is yes, then here you have two options

1-Ask them if you can use them as reference. Don't talk about your ex employer. He doesn't matter. This is between you and them. Don't talk bad about him/her, it doesn't help. If they say yes, you are up to a start

2-If you ask and they say no, then you can make a decision. You can put them anyways and they will be called by your interviewer (not necessary they would talk to him or say good things, it's a risk) or you can just name the companies without a persons name or contact info

Hope this helped! Good luck