Sophomore Renege IBD vs PWM

Guys,

I was just verbally offered a position to work in a small wealth management office where I would be doing meaningful work near my hometown this summer. This is great, because they have agreed to work around my schedule when I take 6 weeks off to attend LSE in July. I verbally accepted the offer on the phone.

However, I just got an email from a friend who works in a well-known boutique in their ER division, asking if I was still interested in being an intern and that he was getting permission from HR to hire me if I was still interested. Of course, I said yes.

Told him about LSE, and that I had verbally accepted an offer at a pwm firm but I am more interested in IB and that if he had a available position, it would be a better fit for me.

This is where things get funky. Should I not have told him about LSE and that I had verbally accepted another offer? The pwm firm usually only hires two people, 1 of them rejected their offer (not sure if he reneged or just rejected) so he asked me if I would be interested and I said yes.

I don't want to burn any bridges, do you guys have any advice on what I can say if I do end up reneging? Should I tell him I got an offer at an IB firm or make up an excuse.

I also interned at an mm IB this past semester if that affects the decision at all.

Thanks