UK Non-Direct Airside Transit visa for Tunisian citizens

I am going to travel from Amsterdam to Peru and have two layovers in London. The first one when flying to Peru, I have five hours to go from Heathrow to Gatwick. The second layover is when I fly back from Peru to Amsterdam It is an airside transfer in the same airport (Heathrow) but I am thinking about booking an alternative flight from Gatwick a few hours later (or maybe one day later) such that I can have enough time to leave the airport and see London.

When I checked on this website I was surprised that Tunisia was not listed under the countries that need a transit visa, neither under the countries that need a non-direct transit visa.

However, on the government website it says that I would need a visa to pass through the UK in transit. But it also adds that if:

• I arrive and depart by air

• have a confirmed onward flight that leaves on the day I arrive or before midnight on the day after I arrive

• have the correct documents for my destination (eg a visa for that country)

and

• you have a common format residence permit issued by an European Economic Area (EEA) country or Switzerland

I might be eligible for ‘transit without visa’. I am studying in Germany so I guess I have the residence permit they talk about.

Do I (Tunisian citizen living in Germany) need a visa in the case of the first layover and is having an alternative flight as described for the second layover sufficient to be able to enter the UK again for a few hours?

I am asking this because of the high costs of UK visas (25% of the total flight price, just for a transfer).