I thought it was common knowledge that 2% shareholders cannot enroll in a 125 plan? I read that if a 2% shareholder is enrolled, it can cause issues for the plan. Does anyone have any practical experience how this is handled? How would this have happened?

Individual over 50 yrs old was a participant in a 401(k) plan for part of the year and put $22,500 into Employer 1's 401(k) plan. Individual then changes jobs and now qualifies to contribute to a 457 plan with Employer [2] Individual plans on maxing out contribution to Employer 2's 457 plan with $24,500 for 2018. Individual has a side job of rehabbing houses via a single member LLC (with no employees) and earned $300,000 there. Individual want to max out and contribute $55,000. It appears that Individual can contribute the $22,500 to the 401(k), the $24,500 to the 457, and the full $55,000 to the SEP for a total deferral to the three plans of $102,000. I have never heard of circumstances similar to this and want to see if anyone has more insight into a provision limiting the deferrals for the three plans that I am missing. This appears to be permissible.