As it seems to be a common problem was wondering if anyone has any ideas to secure popped out front indicator, new ones seem to be around £100.

I had this happen to be 3 or 4 times, thankfully all under warranty. There were some new type of clip that came out that was supposed to solve it, however it stil happened to me.
In the end, the last occasion, the workshop took a closer look at the hole where the indicator went and found that the fibreglass on the inside was not as smooth as should have been. they sanded it down and not had a problem since.
Strangely the problem persisted over 3 different front clams(long story)

Lotus fix is a P clip on it. When mine popped I just used some blu-tak, held it in place really really well for 2 months until it went for a service where they fitted the p-clip.