ILTR from combo of Tier 2 and Exempt visas

Hello everyone, such a great board here, immigration issues are important life problems, and the help provided here is priceless.

I would like selfishly to tap the wealth of knowledge here and as a question, A few bullets below:
- i have spent 3 years on a Tier 2 work visa (working at banks)
- Then i spent 1 year on an EXEMPT visa (working at a bank such as World Bank - they have diplomatic status for employees)
- Then i spent 1 year back on a Tier 2 Visa (working at a bank again).

SO now i have a total of 5 years of continuous employment, but in the middle of it i was working under this special exempt visa (same job as all others, but didnt know they would give me a different visa to Tier 2 at the time...).

Am i able to argue a case to be granted ILTR?

Many thanks!

Not likely, the set o forms clearly state what visas you can combine with tier 2 like work permit, tier 1 etc. Not sure diplomatic visa is included!
Have a look yourself and see whether you qualify, otherwise tgese are cases where a solicitor could argue for you.