commercial generator hook up to TT

All my RV, including bus conversion were always plug to 15 AMP duplex from the house. Even I did not do it often, no problem with running AC in this setup.
So your 15amp adapter should do fine.
General rule in connecting any power is to have breakers off and once everything is plug and check, then flip the breaker.
Generators on start and shutting down do have power surges, so make sure your TT or any RV are disconnected during the procedure.

If you use an adapter, please double check the voltage coming out of it before connecting the trailer. You could lose all the electronics in your rig if you get 240v because of a mis-wired adapter.

Just need an adapter?

Amazon

EDIT: I see you already have the adapter. I'd plug it in, fire up the generator, and using a multi-meter verify the volts coming out. Then just plug in the trailer, and go to town!

I looked your B&S Genny Manual up HERE.

Link may actually bring up Page 11 which states the following about the Locking Outlet:
***
This receptacle powers 120/240 Volt AC, 60 Hz, single phase loads requiring up to 5,550 watts of power (5.55 kW) at 23.1 Amps for 240 Volts or two independent 120 Volt loads at 23.1 Amps each. The outlet is protected by a push-to-reset circuit breaker.
***

There's a diagram of the locking outlet on that page. Looking at this, you CANNOT make max power of 5500W available at 120 Volts, which is what you need. You are limited to half that, 23 Amps, on each of two 120 Volt legs of the generator.

You can't "stack" them and still be 120 Volt!!!

Somebody who knows what they're doing could wire a 30-Amp RV receptacle to ONE LEG of that Locking Outlet. A mistake will send 240 Volts with the consequences you're rightly worried about. Since you can only get about 20 Amps, just use a dogbone adapter to one of your 20A duplex outlets.

Use the 20 amp connector. That is about all you will get anyway. Enough to charge the battery and then run the air. Use propane for everything else or shut the air off.

MsEllie2017 wrote:
I do not want to blow up my electrical system..

Then use a voltmeter. I hope this is just at your home.

Some generators have a 120/240 volt switch

No problem hooking the 30 amp; RV 120 volt to the 120/240 volt outlet.. You just leave one pin NOT CONNECTED (it will be a copper colored pin)

In fact you may be able to buy the needed adapter off the shelf.

White to White or bright to bright (Usually aluminum color)
Green to Green
And just one of the copper (Black or red) to Copper colored screws.

your only going to be able to use (1) hot leg
max 23 amps at 120v

unless you have severe voltage drop on the duplex at the stick house
i would just the stick house 20amp duplex and save the gasoline cost for the generator

if you really need all 23 amps, and buying gas is not to be worried about, go ahead and use the genny, BUT be sure you get or make the correct adapter
only 3 wires, 1 white, 1 green, 1 black
do not use (2) hots and burn out TT applances such as the converter, the fridge , the TV , the water heater etc.. with 230v

I am pretty good with wiring and I am still confused with lot of replies.
Thinking about OP issue again, getting adapters from commercial 240 to RV 120 is not popular set up and I bet even lot of electricians can be confused with it.
So another suggestion >>> hook up your house to generator and plug TT to house duplex.
Another confusion is 20 v/s 15 amp. All step-down adapters I have seen for RV 30 amp plugs are rated 15 amp. I am pretty sure they will carry 20 just fine, but official rating is official rating.

Thank you all for your input. I wanted to hear "sure no problem-go for it but I didn't get that. Which is fine. I had the gen. serviced Monday and my husband was supposed to ask the tech. but he forgot, hence the forum. I am most comfortable with the 20 amp duplex suggestion. All I need is a fan and a TV to find out what I happening in the world and maybe when we will get our electricity back. We have about 40K miles on this tt, I love it and want to use it a few more times. Happy trails.