artists_beware | Here's a Tricky One: Webcomics and Guest Comics

A couple weeks ago, one of my favorite webcomic folks -- in my eyes, THE webcomic guy that started me down this crazy, woolly path -- was asking for guest comics that he could run during his usual weekday schedule while he was orchestrating a big personal life event (nothing permanent, but just disruptive enough that he wanted some guest strips) Also, he wanted them rather quick.

Being an opportunist and trying to quickly draw up a good showing of my stuff (because guest comics for a webcomic == publicity the same way a guest post on a blog does), I made a single-panel comic for him and sent it to him the next day. I'd post it here, except I don't feel like revealing the identity of the guy or his comic yet.

So I waited, patiently checking his RSS feed for the comic (which I was already subscribed to before all this, hence how I discovered the opportunity so fast), day, after day, after day... it didn't show up. Two days after I sent mine, he even went asking for MORE comics, but still without showing mine.

I sent another email Thursday with a copy the comic again, this time asking if he could at least respond back to let me know when I could expect to see mine show up and that I was really anxious to see it / a really big fan of his. No response.

Today, normal comics resumed. I've received no response and no indication that my comic ever has / ever would appear on the site.

I'm probably going too far in protecting the guy's identity at this point (though I imagine a few of you have figured it out already), but that's because it's time for me to ask you guys for advice. I realize it's his prerogative to decide which comics he wants to let appear and which ones he doesn't, but leaving me "waiting by the phone" as it were is a bit much. If he didn't want to run it, he should have said so. There were photoshopped comics and copy-paste comics running during that time period, so it's not like he was looking for a minimum art standard...

I'm mostly annoyed because not only did I take time out of my usual drawing time to produce what basically amounts to fanart (which I can't sell / promote otherwise because it's not my characters involved... hell, until I'm willing to name names, I can't even POST IT on my art sites), but also I've received no response from the guy at all. Not even something as innocuous and banal as a post on his blog or anything stating "We had so many good comics sent in, but we just couldn't show them all!" Even if this is "Standard procedure" for guest comics, it's sue as heck not encouraging me to draw any more of the things, which is only shooting myself in the foot as far as I'm concerned because again, it's as much a way to help another artist out as much as it is a publicity stunt.

I'm also in the sticky situation of wanting to point out that this guy basically refused to post my work without any explanation and that I expected better out of a "professional", but NOT wanting to do so in a way that's going to cause drama. He's a fairly long-lived fellow, which makes me "Ye Ole Noob" and basically means I'm likely to get the majority of the shit thrown back in my face for daring to insist that I should at least have received some sort of acknowledgment for my work.
So... advice?